THE LABORATORY CHEMICAL HYGIENE PLAN
DEPARTMENT OF CHEMISTRY
UNIVERSITY OF TENNESSEE - KNOXVILLE

As of 1 Jan 2005, this web page will be the primary version of the UTK Chem Dept. Chemical Hygiene plan.

Ver. 1 September 4, 1996
Web version: Feb 2003
Last revised: Jun 2016
Contact for this document:
    Prof. Brian Long,
long@utk.edu
    Chemical Hygiene Officer, Dept. of Chemistry, University of Tennessee, Knoxville TN 37996-1600.

University of Tennessee Chemical Hygiene Plan. Copyright 1994, 2003, 2004 by the Department of Chemistry, University of Tennessee, for this page and all linked pages.
Please email Prof. Brian Long long@utk.edu (Chemical Hygiene Officer) for permission to copy.

TABLE OF CONTENTS

I. Introduction
II. Emergency response data
III. Emergency preparedness planning
IV. Hazardous materials information
V. Departmental chemical hygiene officer: definition, duties, responsibilities
VI. Training
VII. Medical consultation
VIII. Employee monitoring
IX. Chemicals requiring approval for use
X. Hazard control procedures
XI. Laboratory fume hood specifications
XII. Specific personal protective equipment
XIII. General laboratory safety procedures
XIV. Provisions for the control of flammable liquids
XV. Hazards associated with compressed gas cylinders
XVI. Substances that present an explosive hazard
XVII. Some commonly found potentially explosive and shock sensitive chemicals
XVIII. Substances with corrosive or irritant hazards
XIX. Substances with acute or chronic toxicity hazards
XX. Cryogenic substances
XXI. Water reactive chemicals
XXII. Pyrophoric (air reactive) chemicals

Appendix 1. Laboratory Inspection Sheet and Explanation of Areas of Inspection for the Chemistry Department
Appendix 2. Listing of Chemicals Sorted by PEL for which a PEL has been established by OSHA
Appendix 3. Listing of Chemicals Sorted Alphabetically for which a PEL has been established by OSHA
Appendix 4. OSHA SECTION 1910.1450 "Occupational Exposures to Hazardous Chemicals in Laboratories"
Appendix 5. OSHA SECTION 1910-Z "Toxic and Hazardous Substances."



I. INTRODUCTION

In recognition that individuals who work in laboratories are potentially exposed to a wide variety of hazardous chemicals, the Tennessee Occupational Safety and Health Administration (TOSHA) has adopted a regulation entitled "The Occupational Exposure to Hazardous Chemicals in the Laboratory Standard" (29 CFR 1910.1450). A main requirement of the regulation is the development of a written document to be referred to as the Chemical Hygiene Plan. The Plan as described in section (b) of the regulation "means a written program developed and implemented by the employer which sets forth the procedures, equipment, personal protective equipment and work practices that are capable of protecting employees from the health hazards presented by hazardous chemicals used in that particular work place".

In response to the regulation, the enclosed document has been developed for use in the Department of Chemistry to insure compliance with the regulation and to protect employees from health hazards associated with exposure to hazardous chemicals.

University of Tennessee, Policies on Safety and Health, Subject:B Responsibilities of Department/Unit designates the head of the unit as the authority responsible for implementation of the program and enforcement of the requirements within the unit.

For purposes of this document, the Chemistry Department is considered a single Laboratory facility, contained in Buehler Hall and the Dabney Addition inclusive, with the exception of certain rooms under the jurisdiction of the Ecology Program (BU 568, 657, 478, 480, 481). It also includes certain rooms in the Science and Engineering Research Facilty (SERF), including SERF 230(nmr), 225+226 (Musfeldt), and 437 (Feigerle).

Within the Chemistry Department, there are rooms not used for chemical handling or storage, such as offices and certain classrooms. It is noted that rooms in the Laboratory have varying requirements for chemical hygiene, based on whether they are used primarily for carrying out chemical reactions ("wet labs"), for storage of chemicals with no facilities for reactions ("storerooms"), for instrumentation primarily, with only small quantities of chemicals present ("instrument labs"), for training of students who are not generally familiar with chemistry and are running only set reactions ("teaching labs"), or for lecture- demonstrations, where reactions are run only by a trained chemist in the presence of a class.

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II. EMERGENCY RESPONSE DATA

-Any emergency: Dial 911.

The official University response organization is the Knoxville 911 center. This alerts the Knoxville City Police and Knoxville Fire Department. If the situation allows further time to communicate, also call 4-3114 to contact the Campus Police Department directly (although the 911 center will alert them later as well). Any situation deemed to be an emergency should be reported immediately to the 911 Center by dialing 911 from any telephone connected to the University telephone system.

- The Chemistry Chemical Hygiene Officer is Prof. Brian Long,
BU 320, Office Phone: 974-5664, Cell 512-653-1885. <long@utk.edu>

- The Head of the Department of Chemistry, Prof. Chuck Feigerle
Office Phone 974-3141, Home Phone 692-8778, Cell 686-2811 <cfeigerle@utk.edu>

Other personnel who should be contacted in emergencies include:

- The Associate Head of the Department of Chemistry, Prof. Shawn Campagna
Office Phone 974-3141, Cell 609-213-2193 <campagna@utk.edu>

- The Chemistry Department Liaison with Facilities Services (formerly Physical Plant) is Mr. Johnny Jones,
(non-chemical emergencies) Office Phone 974-3145, Cell 423-215-5220 <jcjones@utk.edu>

- The faculty member in charged of the room or area where the situation exists. This is required to be posted on the door placard on the door of all lab rooms in the Department.

-The Campus Department of Environmental Health and Safety support personnel can be contacted by calling 974-5084 during normal office hours or by contacting the University Police Department at 4-3114 during non-office hours.

Support Personnel:

Campus Environmental Health and Safety Office {Phone 974-5084}:
Interim Director: April Case <acase3@utk.edu>
Health & Safety Team Leader: Pam Koontz <pkoontz@utk.edu>
Fire Prevention Supervisor: Suzanne Homes
Health & Safety Specialists (Hazardous Waste and Lab Safety):
Scott Moser <smoser@utk.edu>
University Wide Safety Director: Sara Philips {Phone 974-2370}p>
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III. EMERGENCY PREPAREDNESS PLAN

The most important single consideration for emergency preparedness is to plan for possible failures before any experiment is even started. The researcher must anticipate any possible failure mode (including external events such as power outages and building evacuations) at any time during a procedure, and have a plan ready for stabilizing any hazardous situation that results. This must be an integral part of the design of any experiment.

FIRE

The principal concern in any fire is injury to personnel. Clothing fire resulting from a spill or flash fire is the most serious danger to an individual.

If a fire breaks out, certain steps should be followed:

1. Has anyone been burned or is in danger of being burned? Always value life first, seeing that injured persons are removed from the area. This should be done only if serious risks to the rescuer is low. If a victim is on fire from a chemical reaction, get the victim under a safety shower or pour copious amounts of water on the victim while removing any contaminated clothing which could refuel the flame. Make sure that no sparks remain in the clothing.

2. After all individuals are removed:

a. Pull the building fire alarm to warn others of the hazard. This notifies Knoxville Police, UT Police, and the Knoxville Fire Department. If possible, this should be delegated to a second person while rescue of persons at hazard is being done.

b. Notify Chemistry Department personnel of the problem, specifically the Chemistry Chemical Hygiene Officer (Prof. Long), the Head (Prof. Feigerle), or personnel in the Main Chemistry Office (BU 552, 4-3141) who can notify the proper personnel.

c. If none of these can be contacted immediately, notify 911 (Knoxville Police) of the situation. They will in turn contact the Fire Department. Do not attempt to fight a fire which has become large or contains reactive materials. If the fire can be contained, locate the nearest fire extinguisher and follow directions for that particular unit. DO NOT use water extinguishers or water hoses on fires involving flammable liquids or which contain water reactive materials.

EXPLOSIONS

It is the policy of the Department of Chemistry that some appropriate form of eye protection must be worn, whenever handling chemicals or overseeing chemical reactions. In addition, explosion-proof shields are recommended for protection of the lab worker.

If an explosion occurs:

- Immediately evacuate the area of all personnel, because it is possible that some toxic vapors may be released.

- After exiting the room, close all doors behind you.

- Immediately notify the pertinent Chemistry Dept. personnel, then Knoxville Police at 911 for emergency service.

- Under no circumstances should persons re-enter the room unless it is ABSOLUTELY necessary!

SPILLS

Chemical spills in the laboratory can be as minor as a few drops or as major as many liters. In the case of small spills, use logical judgment in cleaning up the spill.

- Use absorbent spill material designed especially for such clean up. This material is available in small amounts in the Spill Cleanup Kit located in the Liquid Nitrogen room, BU 221. A large sack of vermiculite, also effective at absorbing chemcial spills, is available in there, as well. If a group wishes to stock this material in their own area, commercial clay "kitty litter" is a good substitute (the cheapest, non-odorized variety).

If spill clean-up material from the Departmental stocks are used, you must notify the Chemical Hygiene Officer (Prof. Long) within 24 hours, so the material can be replenished.

- Do not re-use any spill clean-up material.

- Bag and seal the material, then dispose of it through the normal Chemical waste disposal procedure, treating it as the category of material absorbed.

In the case of larger spills, immediately contact the Chemistry Chemical Hygiene Officer (Prof. Long) or the Head (Prof. Feigerle) or personnel in the Main Chemistry Office (BU 552, 4- 3141) who can notify the proper personnel. If none of these can be contacted immediately, notify Campus Police at 911 or the Department of Environmental Health and Safety at 4-5084. Be sure to inform them of the nature of the spill and the amount. Be sure to evacuate all individuals from the affected area.

RUNAWAY REACTIONS

The laboratory worker or chemist handling exothermic or runaway reactions must know when to stop trying to control things and do something positive for both his or her own protection and that of others in the room. All reactions of this type, as well an any which may involve flammable or toxic vapors or gases, should be run in a ventilated hood with the doors/sash at the appropriate height to contain the vapors. At the first indication of trouble, the hood doors/sash should be closed and the chemist should carry out the pre-prepared plan of action (constructed during the design phase of the experiment) involving control, if possible, and certainly evacuation. The lab worker should contact the Chemistry Chemical Hygiene Officer (Prof. Logn) or the Head (Prof. Feigerle) or personnel in the Main Chemistry Office (BU 552, 4- 3141) who can notify the proper personnel. If none of these can be contacted immediately, notify the Knoxville Police Department at 911 describing the problem in detail.

CHEMICAL SPLASH

In any laboratory, the chance of chemical or reaction splash upon the student or employee is always present. Before beginning any reaction, the laboratory worker should be familiar with the availablity of safety showers or emergency eye washes.

It is the policy of the Department of Chemistry that some appropriate form of eye protection must be worn by all personnel present, whenever handling chemicals or overseeing chemical reactions.

If a chemist, student or other worker is splashed with a chemical, they should wash the affected area for at least 15 minutes and remove any clothing which is contaminated, but only if possible without tearing the affected body part. Contact Knoxville Police at 911 for prompt medical attention.

Note that the small eye-wash bottles on the wall in some rooms do not contain enough liquid for a complete eye rinsing by at least a factor of ten, and can treat only one eye at a time. They should be used only for the first few seconds of treatment, until a regular eyewash can be reached. Although all laboratories should contain a plumbed-in eyewash, if a room does not contain a regular double eyewash at a sink, there should be a long rubber hose attached to a gooseneck spigot at at least one deep sink in the room, to use as an eyewash.

Contact lenses are strongly discouraged for wear in any lab.

GAS LEAKS

NATURAL GAS LEAKS

If natural gas odors are detected:

- Immediately check all gas outlets for closure.

- If the outlets appear to be all closed, but the gas odor is still detected, check adjacent areas for the use of alkanethiols, especially 1-propanethiol and 1-butanethiol. These are used to add odor to natural gas, but are often encountered in a laboratory environment as themselves, and can be mistaken for natural gas.

- If the gas leak is not found, and the odor cannot be identified as due to alkanethiol use, then open all ventilatory windows, close the room doors and evacuate the premises. Immediately notify other building occupants as to the danger and arrange for an orderly evacuation. Notify Knoxville Police at 911 of the danger and wait for emergency crews to arrive and locate the danger.

COMPRESSED GAS CYLINDER LEAKS

Cylinders that develop leaks should be treated as follows. Cylinder valve packing leaks of corrosive gases such as chlorine, hydrogen chloride, and sulfur dioxide can usually be corrected by tightening the valve packing nut. If valve leaks persist or if leaks appear at any portion of the cylinder, advise the supplier immediately and, if possible, place the cylinder in a fume hood. If the cylinder is too large to fit in a fume hood, place the cylinder by an open window using maximum precautions not to drop or further damage the cylinder. If no window is available, or if the air flow from an open window is into the room, the cylinder should be placed as near as possible to the hood.

On rare occasions, emergency action may be necessary in order to move the leaking cylinder outdoors where it can vent safely. In such situations:

(1) properly warn all personnel required to evacuate the area;

(2) shut off all electrical power to prevent ignition of a leaking flammable gas;

(3) determine shortest route to point of gas disposal; and

(4) post area where cylinder is venting to prevent tampering by unauthorized personnel.

SUMMARY

As with any disaster plan, these are only a sampling of problems which may occur. In any event, common sense should be a guide to efficient and safe handling of any problem. Most importantly, there must always be a disaster plan formulated for contingencies before any experiment is initiated.

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IV. HAZARDOUS MATERIALS INFORMATION

This section of the Chemical Hygiene Plan has been designed to provide pertinent information that can be used by workers to increase their knowledge of the protection parameter available. The description of the type of information available includes:

1. The Department Chemical Hygiene Plan - This present document constitutes the web version of the Department's Chemical Hygiene Plan. Anyone in the University community is entitled to print a copy for their own needs, and every effort will be made to keep this web version content-identical to the master copy. The master copy is maintained on disk in the office of the Chemical Hygiene Officer (Prof. Logn, BU 320).

2. The Occupational Exposure to Hazardous Chemicals in the Laboratory Standard and Appendices is presented as Appendices 4 and 5 of this document.

3. A copy of the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PEL) and the American Conference of Government Industrial Hygienist (ACGIH) Threshold Limit Values (TLV) are available in the Chemistry Reading Room, BU 653, and in the office of the Chemical Hygiene Officer (Prof. Long, BU 320).

4. The best source of descriptions of the signs and symptoms of the body's reactions to exposure to chemicals is the Safety Data Sheet (SDS) for the particular chemical. The SDSs for the chemicals used in the Chemistry Laboratory are available in a file cabinet in the Dry Ice room, BU 220. The Aldrich Safety Data Sheet collection, a bound volume of many common SDSs, is also available in the Chemistry Reading Room, BU 653. If the desired information can not be located in the files, the Chemical Hygiene Officer (Prof. Logn, BU 320) should be contacted for assistance.

5. Reference materials relative to the hazards, safe handling, storage and disposal of chemicals are available in the following locations:

a. The Department's reference library located in the Chemistry Reading Room, BU 653.

b. The Department of Environmental Health and Safety at 2110 Terrace Ave., 974-5084. Contact Person - Ms. Pam Koontz, Health and Safety Team Leader;

c. The University Wide Safety Office. Contact persons - Ms. Sara Phillips, (974-2307).

d. The University of Tennessee Library.

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V. DEPARTMENTAL CHEMICAL HYGIENE OFFICER - DEFINITION, DUTIES AND RESPONSIBILITIES

The Occupational Exposure to Hazardous Chemicals in Laboratories (CFR 29 1910.1450) defines a Chemical Hygiene Officer as: "an employee who is designated by the employer, and who is qualified by training or experience, to provide technical guidance in the development and implementation of the provisions of the Chemical Hygiene Plan. This definition is not intended to place limitations on the position description or job classification that the designated individual shall hold within the employer's organizational structure".

The Chemical Hygiene Officer will be responsible for coordinating the implementation of the Chemical Hygiene Program within the Department and perform duties to include:

1. Develop a written hygiene plan to be submitted to the campus and University Safety Office for approval;

2. To perform periodic reviews, at least annually, of the plan and to prepare revisions to keep the plan current relative to the regulation and University safety policy;

3. To coordinate the necessary activities required to insure that an adequate emergency reaction response capability exist within the department;

4. To coordinate a program to insure that all hazardous materials information resources as required by the regulation are available to Department employees and that the contents of these materials are maintained in a current status;

5. To coordinate the conduction of all training of Departmental employees to insure compliance with the regulation and impartation of adequate orientation to enable them to protect themselves against the potential adverse effects of exposure to hazardous chemicals;

6. To coordinate the procurement of necessary medical consultation to satisfy the requirements of the "medical consultation and medical examinations" section of the standard;

7. To coordinate the arrangements for performance of all required employee monitoring to satisfy the requirements of the "employee exposure determination" of the standard;

8. To coordinate the implementation of the approval procedure for those substances that are designated as requiring prior approval before use; and

9. To coordinate all other activities that are shown to be necessary to insure compliance with all aspects of the standard.

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VI. TRAINING

The Chemical Hygiene Training Officer for the Department of Chemistry is Prof. Brian Long and can be contacted at 974- 5664, BU 320 <long@utk.edu>. All new employees will be thoroughly instructed in the appropriated procedures to limit exposure to hazardous chemicals before beginning to work. In addition to the required training provided by the Department Chemical Hygiene Officer, employees are encouraged to take advantage of special training opportunities that may be available from the Department of Environmental Health and Safety and other organizations.

The required training program shall at a minimum include coverage of the following topics:

1. Orientation to the contents of the Chemical Hygiene Plan and the objectives of the TOSHA Standard (29CFR 1910. 1450)

2. Thorough orientation in regard to the hazardous chemicals that may be encountered and where they are found

3. The long and short term effects the hazardous chemicals may cause

4. Methods and observations that may be used to detect the presence of release of a hazardous chemical in the work environment. Examples:
-monitoring via instrumentation
-sensory observations
-changes in weights, volumes, etc.

5. The physical and health hazards of chemicals in the work area to include a thorough discussion of the type of information available from SDSs.

6. The measures employees can take to protect themselves from potential hazards to include:
-general work practices
-emergency procedures
-use of fume hoods and other control equipment
-selection, use and care of personal protective equipment
-selection, use and maintenance of respirators
-personal hygiene
-first aid and emergency medical care

7. Medical consultation and medical examinations provisions as specified in section (g) of the TOSHA Standard (29CFR 1910. 1450)

A record of all training activities will be maintained in the files of the Departmental Chemical Hygiene Officer with a copy forwarded to the University Department of Environmental Health and Safety. The record at a minimum should contain a session title, date, time, location, the instructors name and a role of all attendees.

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VII. MEDICAL CONSULTATION

The University will provide all employees who work with hazardous chemicals an opportunity to receive medical attention as warranted and in compliance with Section (g) "Medical Consultation and Medical Examinations" of the TOSHA Standard, Appendix 4 of this document. Employees are encouraged to review this section and become familiar with the specifications.

This medical consultation and examination can occur upon (a) development of signs or symptoms by the employee of exposure to a specific chemical hazard, (b) where routine levels of exposure exceed approved levels, or (c) after an unusual event such as a spill, leak, or explosion where there is a likelihood of a hazardous exposure by the employee.

Addendum May 1991 per Murray Edge:

Non-University employees and students shall bear the expense for medical surveillance and treatment in the event of an accidental exposure to a hazardous chemical. These individuals may contact the University Public Safety Department to request access to filing appropriate claims for compensation pursuant to the guidelines set forth by the Tennessee Claims Commission.

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VIII. EMPLOYEE MONITORING

Employee monitoring will be performed as prescribed by Section (d) "Employee Exposure Determination" of the TOSHA Standard, Appendix 4 of this document. Employees are encouraged to review this section and become familiar with the specifications.

The Chemistry Department has established criteria for the use of chemicals which are both hazardous and sufficiently volatile for their vapor to be hazardous. The usage of any such chemical in a properly functioning fume hood, with the sash at the allowed level, using approved practices for the handing of the chemical, will prevent employee exposure to any level of vapor at or above the PEL or TLV limits decreed. Appropriate protective equipment, such as rubber gloves and eye protection, must be worn.

In rooms devoted to teaching in the Laboratory, a situation exists where chemicals are not always used solely in a hood. Likewise, occasionally there will be chemical transfers or exposures outside a hood in the research facilities. A safe usage level for such situations can be calculated based on the OSHA Permissible Exposure Levels (PEL). Such a calculation is presented here for a likely problem area, the Organic Teaching Facility, BU 632.

This room has a volume of approximately 12 x 16 x 3 m = 576 m3. There are three full-sized fume hoods, which operate at ca. 30 linear m/min on a face area of 1.3 m x 0.5 m = 0.66 m2. This corresponds to 20 m3/min. There are also 44 "mini-hoods", one per student station, of ca. 0.04 m2 area. At 30 m/min velocity, this yields 0.12 m3/min per mini-hood. The total air turnover is thus 3 x 20 m3/min + 44 x 0.12 m3/min = 65 m3/min air turnover. In one hour there are thus 65 m3/min x 60 min / 576 m3 = 6.8 room volumes of air turnover. This is typical of most rooms; the design for the renovated Dabney/Buehler rooms is for 12-16 air turnovers/hour.

In this room, there are 576 m3 x 1000 L/m3 / 24.4 L/mole of air at 25C = 23606 moles of air. For a chemical to reach a PEL of 100 ppm, this would require evaporating 2.36 moles of compound into that volume. However, at 10 turnovers/hour, it would require 23.6 moles of the same compound evaporated over that time to reach the PEL. Although local concentrations at the evaporative site could logically be higher than this, because the site of evaporation is proximate to the mini-hood in the experiments performed, this compensates for the locally higher concentration. Also, since recovery of product is the goal of all such experiments, it is unlikely that all of a given compound in use will be evaporated; a loss of more than 20% of the amount of a compound in use is not expected, with the exception of some volatile solvents. We thus set the use of compounds with PELs at 50 ppm or higher as acceptable, with accompanying efforts to restrict loss to the vicinity of a mini-hood as much as possible, and to contain such compounds in closed vessels as much as possible. Use of compounds with PELs of 1000 ppm or more in a open room is restricted only to the extent that good lab practice dictates.

Appendices 2 and 3 present the PELs of a variety of compounds present in OSHA Standard Part 1910 - Subpart Z-1-A. and Z-2, sorted both alphabetically and by PEL levels. These are chemicals that are likely to be used in the Department for which an OSHA PEL or and American Conference of Government Industrial Hygienist TLV has been established. For other hazardous chemicals which are used, the specific SDS for the substance should be consulted for permissible exposure criteria.

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IX. CHEMICALS REQUIRING APPROVAL FOR USE

There are certain chemicals used in the Chemistry Department that due to their particular hazardous nature require an evaluation of the proposed protective procedures before any activity involving handling of the chemical is commenced. If you plan to work with any of the chemicals appearing on the attached listing, you must complete the "Permission for Chemical Use" form form and submit it to Prof. John E. Logn, Departmental Chemical Hygiene Officer for review. The proposed procedure for safely handling the substance will be evaluated by the Hygiene Officer and a recommendation for approval or rejection by Prof. Craig Feigerle, Department Head, or his designated alternate, will be drafted. In no circumstance can work with the chemical be started prior to granting of approval.

The Chemical Hygiene Officer will monitor the acquisition of these via the Chemistry Purchasing Office. All chemical purchases will be logged in, with information concerning date of purchase, quantity, and the research group involved.

(ACUTELY HAZARDOUS CHEMICALS)

The listing provided below is to provide an idea of the types of materials that should be considered as an acute hazard and would warrant approval before use. The Chemical Hygiene Officer should review the Department's chemical inventory listing and designate the acutely hazardous materials actually present. The listing should be reviewed as necessary to keep it up-to-date.

Chemicals Listed in OSHA Standard 1910 - parts of Z-1 plus Z-2 and Z-3.

These constitute the original "dirty dozen" known potent carcinogens, plus additional ones and some highly toxic compounds.

Known Carcinogens
4,4'-methylene-bis(2-chloroaniline)
2-Acetylaminofluorene
Acrylonitrile
4-Aminobiphenyl
Asbestos
Benzidine
Bis(chloromethyl) ether
3,3'-Dichlorobenzidine
4-Dimethylaminoazobenzene
Methyl chloromethyl ether
alpha-Naphthylamine
beta-Naphthylamine
4-Nitrobiphenyl
N-Nitrosodimethylamine
beta-propiolactone
Vinyl chloride
1,2-Dibromo-3-chloropropane
Ethyleneimine

Toxic Gas
Arsine
Fluorine
Hydrogen cyanide
Hydrogen selenide
Phosphine

Shock Sensitive Compounds
Picramide
Picric acid
Nitrate esters, such as nitroglycerin
Benzoyl peroxide
Acetyl peroxide

Extremely Flammable Compounds
Carbon disulfide
Ethylene oxide
Arsine

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X. HAZARD CONTROL PROCEDURES

All necessary control measures will be applied to procedures conducted in the Chemistry Department to insure that no employee is exposed to concentrations of chemicals above the TOSHA PEL or other applicable exposure criteria. As a standard practice, hazardous chemicals will be handled in properly designed, maintained and operated fume hoods or glove boxes whenever possible. Operations involving chemical handling which cannot be performed with the application of these engineering controls will be evaluated by the principal investigator in consultation with the Department's chemical hygiene officer to determine the safest method of performance. Consideration will be given to at least the following parameters:

1. The potential for exposure of individuals outside the confines of the room and appropriate warnings;

2. The need for respiratory protection;

3. The need for other personal protective equipment such as eye, body and hand protection. All personal protective equipment will be selected, used and maintained in recognition of the hazards of the particular chemical(s);

4. The requirement for exposure determination as specified in Section (d) "Employee Exposure Determination" of the TOSHA Standard;

5. Required personal hygiene procedures; and

6. The availability of emergency equipment and formulation of any specific emergency response criteria.

The SDS for the particular chemical(s) and other pertinent reference data will be used to select the safest method of handling the chemical(s).

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XI. LABORATORY FUME HOOD SPECIFICATIONS

A laboratory fume hood is a tool which, if properly used and maintained, allows researchers to work safely with hazardous materials. All fume hoods used to handle hazardous chemicals in the Chemistry Department will be of acceptable design and maintained to meet minimum safety requirements. The use practice will be in accordance with generally recognized good safety parameters.

DESIGN CRITERIA

1. The material the unit is constructed of must be compatible with the particular chemical(s) to be used and resistant to significant deteriorating characteristics of the substance(s) to be handled.

2. The material and method of construction will be amenable to efficient decontamination. All units will be equipped with properly designed air foils and adjustable air flow pattern control slots.

3. The exhaust duct will be installed so as to take the shortest, most direct route through the building to a suitable discharge point outdoors.

4. The duct material will be compatible with the chemical(s) to be exhausted and resistant to any deteriorating characteristics of the substance(s). Duct sections will be joined in such a manner that a durable gas-tight seal will be produced.

5. All duct terminations will be thoroughly evaluated to insure that the possibility of exhausted contaminants being drawn back into the building through fresh air intakes, etc. is minimized.

6. The duct stack shall terminate at a point well above the roof line and in a manner that will promote good dispersion away from the facility. Stacks shall extend at least six feet above the adjacent roof line or any other building component that would tend to retard dispersion.

7. No fitting or geometrical design that would tend to impede the upward dispersion pattern of the exhausted gases will be permitted at the stack termination.

8. The fume hood fan shall be located as close to the end of the duct as possible and preferably on the roof. If the fan(s) is located in an attic, the space shall be mechanically ventilated to the outdoors and considered as a potentially hazardous location. In no instance will it be permitted for the fan to be located on top of a hood or any other location such that a positive pressure could be created in the duct leading to a potential leak of contaminants into the building.

9. The fan shall be of a design and construction that is compatible with the chemical substances to be exhausted. Attention will be given to explosion possibility of flammable vapors and the corrosive nature of many chemicals. Fans, motors and drives shall be located so that safe and easy access for periodic inspection, servicing and maintenance is possible.

10. The fan shall be of a design, installation and maintenance that will be capable of producing a minimum duct velocity of 2,000 feet per minute (10 m/s). The hood face velocity at a practical working opening width of the sash (not less than 12 inches) shall be maintained at an average of 100 linear feet per minute (0.5 m/s) with the velocity at no point being less than 80 linear feet per minute (0.4 m/s). The air flow velocity shall be consistent and not fluctuate more than 15 percent at any point across the sash opening.

11. All hoods will be equipped with a functional light or other indicating device that will indicate whether or not the fan is operating. Hoods used with acutely hazardous materials should be equipped with a velocity monitor that will notify of a velocity drop below the minimal safe level.

In the Chemistry Department, an adequate monitoring device is a strip of Kleenex or Kim-wipe 1" wide and at least 4" long, attached to the bottom of the hood sash by tape. This can be observed throughout the room (and ideally from the door before entry) to indicate by the angle at which it is deflected into the hood, both the proper operation of the fan motor and the approximate velocity of air flow.

CHEMISTRY DEPARTMENT PERSONNEL MUST VERIFY THAT A HOOD IS WORKING BEFORE CARRYING OUT ANY PROCEDURE IN IT!

12. Hoods will be located in such a manner that external air currents will not adversely affect the capture capacity. Air supply inlets to the area will be of proper design and located as to not interfere with the capture capability. Hoods will not be located near doorways, openable windows or adjacent to pedestrian walkways.

13. The make-up air supply to an area equipped with a hood(s) shall be adequate so as not to interfere with the capture capability of the unit(s).

14. All components of the hood system shall be designed, installed and maintained to comply with all NFPA standards and other applicable fire codes. Attention will be given to fire isolation of ducts, explosive-proof requirements of electrical components, fire suppression and detection equipment, etc.

15. All plumbing components will be designed, installed and maintained to comply with applicable codes. Particular attention will be given to prevention of cross connections by the installation and maintenance of approved vacuum breakers and other appropriate equipment.

16. All components of the hood(s), to include the sash, will be maintained in a state of good repair and in good operating condition.

HOOD USE PRACTICES

1. Before starting work with hazardous chemicals in a fume hood, the user must insure that the unit is functioning properly and that all components are in a good state of repair. At a minimum, the following items should be checked:

a. That the fan is functioning properly and an adequate air flow exists;

b. That the adjustable slots are set to provide the most uniform air flow through the face of the hood;

c. That the hood sash is in good repair and functions smoothly. When working with materials that present a possible explosive hazard, a blast shield should be used in addition to the sash; and

d. That the hood design, construction and maintenance is compatible with the material being handled. Example:
If working with perchloric acid, the hood should be equipped with a decontamination wash-down device.

2. Hoods used to manipulate chemicals should not be used to store significant numbers of chemical containers. The containers tend to disrupt good capture air flow and in the event of an accident, can create increased hazards to emergency personnel and complicate cleanup. Any containers present should be stored at the sides of the hood, to minimize interference with air flow.

3. All necessary equipment, if possible, should be placed in the hood prior to initiation of the handling procedure to prevent the need to open the sash greater than the practical working width during the procedure. The greater the width of the sash opening, the more difficult contaminant capture and control becomes.

4. The equipment should be located as far to the rear of the hood as possible to increase efficiency of capture and control. Procedures should be performed at a minimum of 6 inches inside the hood.

5. Care should be exercised to prevent blockage of the slots with large containers or equipment which would decrease capture capacity. Placing large equipment on riser blocks will help to minimize disruption of air flow.

6. The user must observe good housekeeping procedures. The air passage should be checked regularly for obstructions. All unnecessary equipment and any waste or debris should be removed as soon as possible after generation.

MAINTENANCE AND TESTING

1. Fume hoods should be thoroughly checked (at a minimum) once a year as well as following installation, filter changes, or maintenance activities. The check should include the following:

The air velocity should be measured by making a traverse with an anemometer or velometer in the face plane of the hood with the sash at the practical work opening width. The average should be at least 100 linear feet per minute and the velocity at each point should not vary by more than 15 percent from the average.

2. The seals on light fixtures and other electrical devices should be checked for corrosion and leakage.

3. On hoods with vertical sashes, the sash cords and fittings supporting the counter-weights should be checked for damage.

4. Broken glass should be replaced.

5. Fan drives should be lubricated and fan belts should be checked for proper tension and wear.

6. Airflow failure indicators should be inspected to insure that they are functioning properly.

7. The general condition of the unit as to damage, corrosion, etc., should be observed and any deterioration corrected.

It is the responsibility of Facilities Services personnel who perform the maintenance on the fan motors to verify that the motor is turned back on after such maintenance, and to verify in the room where the hood is located, that the hood is functioning again.

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XII. SPECIFIC PERSONAL PROTECTIVE EQUIPMENT

The specific personal protective equipment to be used for a particular procedure is dictated by the type materials being used and the degree of protection that can be provided by engineering controls such as ventilation, barriers, etc. Before using any hazardous chemical substance, the Safety Data Sheet (SDS) must be thoroughly reviewed to determine the specification for protective procedures and equipment. An example of a prescription for personal protective equipment is the following given for handling sulfuric acid:

Ventilation System:

A system of local and/or general exhaust is recommended to keep employee exposures below the Airborne Exposure Limits. Local exhaust ventilation is generally preferred because it can control the emissions of the contaminant at its source, preventing dispersion of it into the general work area. Please refer to the ACGIH document, "Industrial Ventilation, A Manual of Recommended Practices", most recent edition, for details.

Personal Respirators:

(NIOSH Approved)

If the TLV is exceeded, a full facepiece chemical cartridge respirator may be worn, in general, up to 100 times the TLV or the maximum use concentration specified by the respirator supplier, whichever is less. Alternatively, a supplied air full facepiece respirator or airlined hood may be worn.

A chemical cartridge respirator is not approved for use at Immediately Dangerous to Life and Health (IDLH) levels.

Skin Protection:

Wear impervious protective clothing, including boots, gloves, lab coat, apron or coveralls to prevent skin contact.

Eye Protection:

Use chemical safety goggles and/or full face shield where splashing is possible. Contact lenses should not be worn when working with this material. Maintain eye wash fountain and quick- drench facilities in work area.

- Soft contact lenses should not be worn in any room in the Laboratory, at any time. This is true even if they are beneath other protective eyeware: they are notorious for absorbing irritating and corrosive chemical vapors from the air and holding them against your eyeball. Hard contact lenses are not as bad, but regular glasses are best; they fit under standard goggles.

In any situation where there is doubt as to the control procedures warranted and the personal protective equipment required, the Departmental Hygiene Officer should be consulted for clarification. If the Departmental Hygiene Officer is not confident in providing advice, he should consult with the health and safety resource personnel listed in Section II of this plan.

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XIII. GENERAL LABORATORY SAFETY PROCEDURES

The Fundamental Rule of Safety: Always construct an emergencies contingency plan, when you are planning any experimental procedure, before you do anything in the lab.

1. Know the safety rules and procedures that apply to the work that is being performed. Determine the potential hazards of the materials being used and make sure the appropriate safety precautions are understood and applied.

2. Know the location of and how to operate emergency first aid equipment.

3. Know the proper procedure for alerting emergency management agencies and summoning assistance.

4. Determine the appropriate type of personal protective equipment needed, learn how to properly use the equipment, and learn how to maintain the equipment such that it provides adequate protection. Routine wearing of rubber gloves is encouraged.

5. Be alert to unsafe conditions and actions and call attention to them so that corrections can be made as soon as possible. Work at developing a good safety attitude.

6. Avoid polluting the environment by complying with accepted waste disposal procedures.

7. Do not smoke, eat or drink beverages in areas where research chemicals are present.

8. Be certain that all chemical containers are properly labeled. The importance of proper labeling can not be over-emphasized.

9. Post appropriate warning signs when hazards such as radiation, laser operations, particularly hazardous chemicals, biological agents, etc. are present.

10. Do not participate in any type of horseplay in the Laboratory. The accident potential of such action in the presence of hazardous substances is totally unacceptable.

11. Dress appropriately to reduce the potential for accidents. Wear sturdy shoes, confine long hair and loose clothing. Avoid wearing dangling jewelry.

12. Practice good personal hygiene. Wash hands frequently when known to have been contaminated, before leaving the room, etc.

13. Work areas should be maintained clean and free from obstruction. Cleanup should follow the completion of any operation and/or at the end of each days work.

14. Avoid working alone in the Laboratory and at unusual times of the day. If you must work alone at unusual times, make sure that supervisory personnel are aware of your activity and arrangements are made for handling emergency situations.

15. Inspect equipment and facilities regularly and insure that necessary maintenance is performed. Develop an adequate lockout system to prevent injury from equipment during maintenance procedures.

16. Make sure that all equipment is provided with adequate guards to prevent accidental contact with injury producing components such as cutting edges, heated surfaces, moving parts, etc. Inspect electrical cords for wear or bare wires before using.

17. Make sure that all spilled chemicals are promptly cleaned up and that proper disposal for the resulting waste is arranged.

18. Before leaving the work area for the day, be sure that all equipment and utilities not in use are turned off. Be sure that any reactions that are left to run unattended overnight will not create a hazard. When a reaction must be left unattended, a description of the process to include emergency procedures should be posted near the door on the exterior of the room. The names of responsible persons and their telephone numbers should also be posted near the entrance door of the facility.

CLAMP YOUR WATER HOSES AT BOTH ENDS!!!

BE SURE THAT HOSES CANNOT TOUCH HOT SURFACES!!!

19. Make sure that the work area is maintained in such a condition that no hazards will be presented to custodial and maintenance personnel who may enter during non-working hours. If there are hazards existing, make sure they are properly labeled. Make sure that hazardous materials are not placed in the regular solid waste containers such that a hazard to personnel or contamination of the environment occurs.

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XIV. HAZARDS ASSOCIATED WITH FLAMMABLE LIQUIDS

One of the greatest potentials for serious accidents in a laboratory setting is that of fire. The presence of flammable and combustible liquids, many times in quantities much larger than necessary to meet the objectives of the work to be performed, coupled with numerous sources of ignition, creates a viable potential for fire. In order to control the potential hazard of flammable liquids, the following control practice should be applied:

1. The quantities of flammable liquids present in the work area should be restricted to as small a quantity as possible. A well designed program, coupled with effective training and orientation efforts, can greatly assist in controlling the quantities of material stored in any one room.

2. All flammable liquids should be stored in approved safety cans or flammable liquids storage cabinets. The containers should be properly labeled to denote the contents and to indicate that they contain flammable materials. The storage cabinets must be located as far as possible away from sources of ignition and exit pathways. Large quantities of flammable liquids should be stored in properly constructed storage rooms out of the work area.

3. Flammable liquids requiring refrigeration should only be stored in units which are Underwriters Laboratories (UL) or Factory Mutual (FM) approved as explosive resistant or explosive proof. An ordinary refrigerator should not be used for storage of flammables.

4. Areas where flammable materials are stored and used should be provided with adequate ventilation to control vapor concentration. A fume hood should be used when transferring liquids from one container to another, when liquids are allowed to stand in open containers or heated in open containers.

5. Areas where flammable materials are stored and used should be equipped with adequate fire extinguishing equipment.

6. Areas where flammable materials are present should be restricted for smoking and NO SMOKING signs should be posted.

7. Sources of ignition such as open flames, arcing electrical equipment, static electricity, etc. , must be controlled. All equipment should be UL or FM approved and maintained in a good state of repair. The building electrical system should be installed and maintained in accordance with the National Electrical Code. In those areas where flammable vapor generation is expected, the electrical system should be explosive proof as outlined in the National Electrical Code.

8. Metal containers which are used to transfer flammable liquids to other metal containers should be grounded to prevent the build- up of static electricity. A bonding wire should be attached between the two containers during the transfer process.

9. Pumps used to transfer flammable liquids should be UL or FM approved for flammable liquids transfer.

10. In operations where flammable liquids are transferred from drums by gravity, the drums should be provided with approved venting devices and approved spigots. Catch cans should be provided to catch any spillage from the transfer operation.

11. Flammable substances should never be heated by using an open flame. Preferred heat sources include steam baths, water baths, oil baths, heating mantles and hot air baths.

12. Flammable liquids should not be allowed to come into contact with incompatible chemicals such as strong oxidizing agents which could initiate an ignition due to the chemical reaction.

13. Glass containers of flammable liquids should be protected from breakage as much as possible. The use of plastic coated safety bottles is highly encouraged. Non-plastic coated bottles should be protected during transport by use of an impervious device such as a plastic bucket.

14. It should be remembered that flammable liquids that have been declared waste still possess the same fire characteristics and should be handled with the application of all recommended precautions. All waste material must be disposed of properly. Waste flammable liquids should not be flushed down the drain.

15. Spills of flammable liquids must be cleaned up immediately by absorption with a vapor generation retardant absorbent such as "Oil Dry". Oil Dry is the type absorbent used to control spills of oil in automobile garages. Do not mop up a spill due to the possible generation of static electricity and ignition. All potential sources of ignition should be shut-off as soon as the spill occurs. Non-ignition potential ventilation sources that will tend to dilute solvent vapor without dispersing to other areas of the building should be left operating.

16. Residue from spill cleanup must be managed and disposed of as a hazardous flammable waste.

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XV. HAZARDS ASSOCIATED WITH COMPRESSED GAS CYLINDERS

Compressed gases present a unique hazards in that they have the potential for being hazardous both mechanically and chemically at the same time. Additional hazards can arise from the reactivity and toxicity of the gas, and asphyxiation can be caused by high concentrations of even "harmless" gases such as nitrogen. The large amount of potential energy resulting from compression of the gas makes a compressed gas cylinder a potential torpedo or fragmentation bomb. Careful procedures are necessary for handling the various types of compressed gases, the cylinders that contain them, the regulators used to control their flow and the piping used to confine them during flow.

1. The contents of a cylinder should be identified with decals, stencils, or glued or wired-on tags. Color codes alone or tags hung around the neck of the cylinder are not acceptable. A cylinder lacking the proper identification should not be accepted from the vendor.

2. The hazardous properties of gas (such as flammability, toxicity, chemical activity and corrosive effects) should be determined before the gas is put to use. The user should insure that adequate safety precautions are applied at all times.

3. The protective valve cap should be kept on the cylinder at all times, except when containers are connected to dispensing equipment.

4. Cylinders should not be used as rollers, supports or for any other purpose than to contain the contents as received.

5. Containers should not be dragged, rolled or slid. A suitable hand truck should be provided for transporting large cylinders. The hand truck should be equipped with a chain or belt for securing the cylinder.

6. When a cylinder has been positioned in its place for use, it should be secured to a wall, a bench or some other firm support, or be placed in a cylinder stand.

7. Cylinders should be protected from abuses such as exposure to damp ground, sunlight or other high temperatures, precipitation, direct flame, electrical currents, corrosives, physical damage, etc.

8. Empty and full cylinders should be stored separately. Serious suckback can occur when an empty cylinder is mistakenly attached to a pressurized system. Empty cylinders should be marked to designate their status. Never assume that a cylinder labeled "empty" is so with respect to the opening of the valve or leaving it unsecured. When returning cylinders, close the valve before shipment leaving some positive pressure in the cylinder.

9. Cylinders of flammable gases should be grounded and should be bonded to the equipment they serve to control static electricity.

10. The size of the individual cylinders and the total number of cylinders present should be kept to as small as possible. Toxic, flammable and corrosive gases should be used with local exhaust ventilation (such as a fume hood) whenever possible.

11. When discharging gas into a liquid, a trap or suitable check valve should be used to prevent liquid from entering the regulator and cylinder.

12. Where gases of different types are stored at the same location, containers should be grouped by types of gas and the gases arranged in accordance with the appropriate groups. For example, oxidizers should be separated from fuel gases.

13. Cylinders should not be stored near readily ignitable substances such as gasoline, or other combustibles, including oil.

14. Cylinders should not be located near exits, stairways or in areas normally used or intended for safe exit from the facility.

15. Cylinders should not be located in areas accessible to the general public and should be protected against tampering.

16. Use cylinders only with appropriate matching equipment for the contents. Do not force the connection or use homemade adapters. Standards for design, installation and maintenance of equipment have been developed by the American National Standards Institute (ANSI). Be sure that the necessary sealing adapters are used. For example, some lecture bottles require that a lead washer be installed between the cylinder outlet and the regulator.

17. Do not use a cylinder without an appropriate pressure regulator.

18. Close cylinder valves when not in use. Do not stop the flow from a cylinder overnight by backing off on the regulator. Even the best quality regulators can develop seat leaks and allow excessive pressure to develop in equipment.

19. Never attempt to refill a cylinder by connecting to one of a higher pressure. Cylinders should only be filled by the vendor.

20. Flammable gases must be protected from sources of ignition such as open flames, arcing electrical equipment, smoking, static electricity, mechanical friction, etc. Signs should be conspicuously posted in areas in which flammable gases are present identifying the substances and appropriate precautions.

21. Cylinders should be placed so that the cylinder valve is accessible at all times. On cylinders not equipped with a hand- wheel valve, a valve wrench should be provided in close proximity for emergency flow termination.

22. Cylinder valves should be opened slowly; the valve on an unregulated cylinder should never be "cracked". The valve should only be opened to the extent necessary to produce the desired flow, never fully opened.

23. Cylinder discharge lines should be equipped with approved check valves to prevent inadvertent contamination of cylinders that are connected to a closed system where the possibility of flow reversal exists.

24. All equipment used with compressed gases should be inspected and tested periodically. A record of inspection should be maintained. The use of soap solution or nitrogen pressure to the maximum allowable working pressure of the weakest section of the equipment is an adequate means of testing for leaks.

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XVI. SUBSTANCES THAT PRESENT AN EXPLOSIVE HAZARD

ORGANIC PEROXIDES

Organic peroxides are a class of compounds that have stability characteristics that make them among the most hazardous substances handled in laboratories. As a class, they are low-power explosives, hazardous because of their extreme sensitivity to shock, sparks, or other forms of accidental ignition. Many peroxides that are routinely handled in laboratories are far more sensitive to shock than most primary explosives (e. g. TNT). Peroxides have a specific half-life or rate of decomposition under any given set of conditions. The compounds are sensitive to heat, friction, impact and light as well as strong oxidizing and reducing agents. All organic peroxides are highly flammable, and fires involving peroxides should be approached with extreme caution. A peroxide present as a contaminant in a reagent or solvent can change the course of a planned reaction.

Types of compounds known to form peroxides include the following:

1. Aldehydes

2. Ethers, especially cyclic ethers and those with alpha- hydrogens, form a dangerously explosive peroxide on exposure to air and light. Ethers must never be distilled unless known to be free of peroxides.

3. Secondary alcohols are just as bad as ethers in terms of explosive peroxides being formed.

4. Compounds containing benzylic hydrogen atoms, especially if the hydrogen atoms are on tertiary carbon atoms such as isopropylbenzene.

5. Compounds containing an allylic (CH2=CHCH2R) structure which includes most alkenes.

6. Vinyl and vinylidene compounds.

SOME EXAMPLES OF PEROXIDIZABLE COMPOUNDS

Peroxide Hazards on Storage - Discard After 3 Months
Isopropyl ether
Divinyl acetylene
Vinylidene chloride
Potassium metal
Sodium amide

Some Chemicals Which Form Peroxide Hazard on Concentration - Discard After One (1) Year or Test Routinely
Diethyl ether
Dicyclopentadiene
Tetrahydrofuran
Diacetylene
Dioxane
Methyl acetylene
Decahydronaphthalene
Tetrahydronaphthalene (tetralin)
(Decalin)
Ethylene glycol dimethyl ether
Cyclohexene

Hazardous to Peroxide Initiation of Polymerization Note: polymerizable compounds should be stored cold (<5C) OR discarded after one year!
Methyl methacrylate
Chlorotrifluorethylene
Styrene
Vinyl acetylene
Acrylic acid
Vinyl acetate
Acrylonitrile
Vinyl chloride
Butadiene
Vinyl pyridine
Tetrafluoroethylene
Chloroprene

PRECAUTIONS

1. The handling of peroxide forming chemicals should be limited to the minimum amount possible. All chemicals should be dated when received and disposed of in accordance with good recommended practices.

2. All spills should be cleaned up immediately. Solutions of peroxide can be adsorbed onto vermiculite.

3. The sensitivity of most peroxides to shock and heat can be reduced by dilution with inert solvents such as aliphatic hydrocarbons. However, toluene is known to induce the decomposition of diacyl peroxides.

4. Solutions of peroxides in volatile solvents should not be used under conditions in which the solvent might be vaporized because the peroxide concentration in the solution will be increased.

5. Metal spatulas should not be used to handle peroxides because contamination by metals can lead to explosive decomposition. Ceramic or wooden spatulas should be used.

6. Smoking, open flames and other sources of heat should not be permitted near peroxides.

7. Friction, grinding and all forms of impact should be avoided near peroxides (especially solid ones). Glass containers that have screw-cap lids or glass stoppers should not be used. Polyethylene bottles that have screw-cap lids may be used.

8. To minimize the rate of decomposition, peroxides should be stored at the lowest possible temperature consistent with their solubility or freezing point. Liquid or solutions of peroxides should not be stored at or lower than the temperature at which the peroxide freezes or precipitates because peroxides in solid form are extremely sensitive to shock and heat.

9. Laboratory experiments employing peroxides or peroxide containing solvents should always be carried out behind a shield and with all other recommended precautions.

PICRIC ACID
(C6H3N3O7, Ammonium picrate, 2,4,6,-trinitrophenol, picronitric acid, carbazotic acid, nitroxanthic acid and phenoltrinitrate)

Picric acid normally contains 10-20% water for stabilizing. With the passage of time, the acid may become sufficiently dry (<10% water) to present a potential explosive hazard.

NOTE: Damp picric acid is white; dry picric acid is yellow. If you see a bottle of picric acid that is yellow, handle it extremely cautiously. All supplies of picric acid should be checked monthly for color, and water added as necessary.Note that tetranitrophenol alse falls into this category.

The following safety procedures are recommended for handling picric acid:

1. Keep the amount of acid to as small a quantity as possible. Maintain a record of the date of receipt of the supply and make sure unused acid is disposed of before time can degrade to an unsafe condition.

2. All storage areas and containers should be properly labeled to indicate the contents and cautioning against disturbing.

3. Do not store acid in proximity with materials such as oxidizable materials, metals (particularly finely divided) and alkaloids.

4. Store containers in a well secured area equipped with adequate ventilation.

5. Avoid excessive movement or concussion of picric acid containers.

6. Wear appropriate protective equipment when handling the acid to include chemical gloves, laboratory aprons, eye protection, etc.

7. Do not open a container if the acid appears dry. If crystals roll over each other, this may indicate sufficient dryness to be hazardous.

8. Do not attempt dilution of acid unless through familiarization of the safe procedure to be applied has been performed.

9. Spills of picric acid must be properly cleaned up as soon as possible and the residue properly disposed. If a spill occurs in the sink, flush with copious amounts of water. If the spill is on the counter or floor, cover with sand/soda ash mixture.

10. Make sure that unwanted and particularly old picric acid is properly disposed. The safest method of disposal is detonation by explosives experts.

11. All glassware and equipment contaminated by picric acid should be thoroughly washed with a mild bicarbonate solution, followed by a strong soap solution. Empty, cleaned containers and equipment can be disposed of as regular waste material.

12. Remember that picric acid is a corrosive material which requires the application of the standard acid handling safety precautions. Adequate personal protective equipment should always be worn when handling the acid.

PERCHLORIC ACID

Contact of perchloric acid solution with oxidizable or combustible materials or dehydrating and reducing agents may result in fire or explosion. Persons using the acid should be thoroughly familiar with its hazards and safety precautions should include the following:

1. The quantity of acid should be limited to as small as possible. Only the amount needed for the particular experiment should be allowed in the immediate working area.

2. The acid bottles should be stored in a glass or ceramic dish large enough to catch the entire contents of the bottle if broken. The use of plastic coated safety bottles will further decrease the probability of spillage from a breakage situation. The tray and outside of the bottle should be rinsed daily. When acid has been removed from a bottle, the outside should be rinsed. All glassware contaminated with perchloric acid should be thoroughly rinsed.

3. Laboratory reactions should be performed in a properly constructed fume hood and with the application of safety shields.

4. Laboratory fume hoods should be constructed of non-corrosive material and should be equipped with a water spray wash-down system capable of decontamination. Exhaust ducts should be designed to take the shortest, non-directional change route to an outside point of discharge. Repair work on the system should be performed only after a thorough decontamination procedure has been performed.

5. Contact of perchloric acid solutions with strong dehydrating agents such as concentrated sulfuric acid may result in the formation of explosive anhydrous perchloric acid. In wet combustion with perchloric acid, treat the sample first with nitric acid to destroy easily oxidizable substances. Perchloric acid should be kept away from incompatible organic chemicals.

6. Acid spills should be washed up immediately, using large quantities of water with repeated mopping up and final rinsing of the mopped up material. The acid residue should be neutralized before the final disposal.

7. Electric hot plates should be used instead of oil baths for heating perchloric acid solutions. The heating process must be constantly monitored to insure that the solutions do not become anhydrous.

8. Stored quantities of perchloric acid should be inspected frequently and any acid that shows signs of contamination or discoloration should be properly disposed of as soon as possible. A minimum inspection frequency of once per month is suggested.

9. Any procedure or condition that causes perchloric acid to become more concentrated than 72% should be considered potentially hazardous. Perchloric acid becomes very unstable in concentrations greater than 72%.

ADDITIONAL EXPLOSIVE COMPOUNDS

It would be very difficult to enumerate every chemical which may possess explosive characteristics under every conceivable condition. In general, compounds containing the following functional groups tend to be sensitive to heat and shock:

- acetylide
- azide
- diazo
- haloamine
- nitroso
- ozonide
- peroxide.
Compounds containing nitro groups may be highly reactive, especially if other substances such as halogens are present. Perchlorates, chlorates, nitrates, bromates, chlorites and iodates, whether organic or inorganic, should be treated with respect, especially at higher temperatures. The best recommendations are to be familiar as possible with the hazardous properties of the chemicals with which you are working.

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XVII. SOME COMMONLY FOUND POTENTIALLY EXPLOSIVE AND SHOCK SENSITIVE CHEMICALS

1. Acetylides of heavy metals
2. Aluminum orphorite
3. Amatol
4. Ammonal
5. Ammonium nitrate
6. Ammonium perchorate
7. Ammonium picrate
8. Ammonium salt lattice
9. Butyl tetryl
10. Calcium nitrate
11. Copper acetylide
12. Cyanuric triazide
13. Cyclotrimethylenetetranitramine
14. Cyclotetramethylenetetranitramine
15. Dinitroethyleneurea
16. Dinitroglycerine
17. Dinitrophenol
18. Dinitrophenolates
19. Dinitrophenyl hydrazine
20. Dinitroresorcinol
21. Dinitrotoluene
22. Dipicryl sulfone
23. Dipicrylamine
24. Erythritol nitrate
25. Fulminate of mercury
26. Fulminate of silver
27. Fulminating gold
28. Fulminating mercury
29. Fulminating platinum
30. Fulminating silver
31. Gelatinized nitrocellulose
32. Guanyl nitrosamino guanyl tetrazene
33. Guanyl nitrosamino guanylidene hydrazine
34. Heavy metal azides
35. Hexanite
36. Hexanitrodiphenylamine
37. Hexanitrostilbene
38. Hexogen
39. Hydraziniumnitrate
40. Hydrazoic acid
41. Lead azide
42. Lead mannite
43. Lead monoitroresorcinate
44. Lead picrate
45. Lead salts
46. Lead styphnate
47. Trimethylolethane
48. Magnesium orphorite
49. Mannitol hexanitrate
50. Mercury oxalate
51. Mercury tartrate
52. Mononitrotoluene
53. Nitrated carbohydrate
54. Nitrated glucoside
55. Nitrated polyhydric alcohol
56. Nitrogen trichloride
57. Nitrogen tri-iodide
58. Nitroglycerin
59. Nitroglycide
60. Nitroglycol
61. Nitroguanidine
62. Nitroparaffins
63. Nitronium perchlorate
64. Nitrourea
65. Organic amine nitrates
66. Organic nitramines
67. Organic peroxides
68. Picramic acid
69. Picramide
70. Picratol
71. Picric Acid
72. Picryl chloride
73. Picryl fluoride
74. Polynitro aliphatic compounds
75. Potassium nitroaminotetrazole
76. Silver acetylide
77. Silver azide
78. Silver styphnate
79. Silver tetrazene
80. Sodatol
81. Sodium amatol
82. Sodium dinitro-ortho-cresolate
83. Sodium nitrate-potassium nitrate
84. Sodium picramate
85. Syphnic acid
86. Tetrazene
87. Tetranitrocarbazole
88. Tetrytol
89. Trimonite
90. Trinitroanisole
91. Trinitrobenzene
92. Trinitrocresol
94. Trinitro-meta-cresol
95. Trinitronaphthalene
96. Trinitrophenetol
97. Trinitrophloroglucinol
98. Trinitroresorcinol
99. Trinonal
100.Urea nitrate

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XVIII. SUBSTANCES THAT PRESENT A HAZARD DUE TO THEIR CORROSIVE OR IRRITANT CHARACTERISTICS

This category of irritants is generally considered the most hazardous in causing external injury due to the fact the liquid form is most amenable to tissue-chemical contact. The more concentrated the irritant and the longer the contact, the more rapid and intense will be the damaging process.
Typical Examples of Liquid Irritants

Mineral Acids:
nitric acid
sulfuric acid
hydrochloric acid
hydrofluoric acid
phosphoric acid

Organic Acids:
formic acid
acetic acid
chloroacetic acids
cresylic acid
polyhalogenated acetic acids

Organic Solvents:
petroleum solvents
most alcohols
coal tar solvents
carbon disulfide
chlorinated hydrocarbon solvents
turpentine and terpenes
most liquid esters and ketones

PRECAUTIONS

1. When handling liquid corrosives-irritants, adequate personal protective equipment should be used, to include rubber gloves, chemical safety goggles, face shield as warranted, and rubber aprons.

2. An approved safety shower and eye wash device capable of providing a sufficient quantity of tempered water to flush the skin and eyes for a period of a minimum of 15 minutes should be provided.

3. Spill protection during transportation of containers in the form of plastic coated safety bottles or plastic carrying devices should be employed. In the Chemistry Department, no liquid-in- glass containers will be issued at the Stockroom Window (BU 232) unless the purchaser has a suitable plastic or rubber carrying vessel.

4. Glass containers of corrosives should not be stored above eye level. Ideally, storage shelves should have a rim or lip to prevent the accidental slipping off of a container.

5. Care should be exercised to keep corrosives separated from other incompatible chemicals. An ideal method of storage of acids is in cabinets specifically designed for corrosives.

6. Precautions to prevent inhalation of vapors from the liquid must be made to include use of adequate ventilation and use of approved respirators.

7. Emergency response procedures should be well understood by all individuals involved in the use of corrosives.

8. Always wash hands and any other exposed body parts which could have become contaminated during handling procedures.

SOLID IRRITANTS

The adverse effects of solid irritants depend largely on their solubility in the moisture of the skin or other surfaces. These irritants can cause serious damage, both from their corrosives action and from their thermal heats of solutions. This class of irritants is probably the least hazardous of all the materials handled because a person has sufficient time to remove the material from exposed body surfaces before serious irritation occurs. However, in many cases the irritant is in the form of a liquid slurry and the potential for irritation is increased.

Solid irritants can cause delayed irritation, for example, when solid materials contacts the skin without one's knowledge or when it is incompletely removed following contact. Irritants, such as the caustic alkalis, are not immediately painful, as are the acids, and if left on the skin until pain is felt, serious injury has usually already occurred.

Typical Examples of Solid Irritants

Caustic Alkalis
alkaline sulfides
sodium hydroxide
sodium carbon
sodium silicate
potassium carbonate
ammonium carbonate
barium hydroxide
barium carbonate
trisodium phosphate
lime (both hydrated & dehydrated)
calcium cyanamide

Elements and Salts
elemental sodium
elemental potassium
elemental phosphorus
antimony and its salts
arsenic and its salts
chromium and the alkaline chromates
copper sulfate
copper cyanide
mercuric salts
zinc chloride
silver nitrate
phenol

PRECAUTIONS

1. Precaution to prevent inhalation of dust should be employed to include adequate ventilation and approved respirators.

2. Adequate personal protective equipment should be used to include safety goggles, face shields as warranted, gloves and protective aprons. Protective creams may also be available for selected situations.

3. An approved safety shower and eye wash device capable of providing a sufficient quantity of tempered water to flush the skin and eyes for a period of a minimum of 15 minutes should be provided.

4. Care should be exercised to keep the materials separated from other incompatible chemicals.

5. Good personal hygiene, especially thorough washing of hands should be practiced.

6. Emergency response procedures should be well understood by all individuals involved in using solid corrosives.

Note that phenol is especially dangerous, due to delayed chemical burns!

GASEOUS IRRITANTS

Although liquid and solid irritants afford considerable hazard from skin and eye contact, the most serious hazard associated with irritants in general from materials is the gaseous state.

Widely different symptoms may result from the action of irritant gases and vapors. These differences are due primarily to the specific structures on which the irritant acts. Symptoms are therefore governed by the structures affected by the inflammation as well as by the mode of action of the irritant substance. The site of action of gaseous irritants is influenced principally by the solubility of the irritant. For example, ammonia gas in high concentrations will cause intense congestion and swelling of the upper respiratory passages and possible rapid death from spasm or edema of the larynx. If the immediate effects are survived, there may be little serious aftereffect since the deeper structures of the respiratory tract may not be seriously injured. On the other hand, phosgene, even in concentrations that cause little immediate irritation, may later be fatal owing to chemical pneumonitis or pulmonary edema (filling of the lungs with fluid) through its action on the air cells (alveoli) of the lungs. Chlorine is intermediate (between ammonia and phosgene) in its action.

The selective action of the irritant gases in the respiratory tract determines the relative danger of death from them. The delicacy of the respiratory membranes, their susceptibility to injury, and the seriousness of the resulting damage are very different in the upper and lower respiratory tracts. The action of irritant gases and vapors in the nose and pharynx may produce an intense local reaction by inflammation without immediate danger or permanent damage. It is a more serious matter when the trachea and bronchi are injured. Not only are the local effects painful, but general systemic effects may develop. The most serious results of inhalation of an irritant gas or vapor occurs when the lungs themselves are acted upon. The damage may give rise to an acute edema leading to suffocation or, if this danger is escaped, to pneumonia with prostration and circulatory impairment. The outcome of either process may be fatal.

The harmful effect of an irritant is not a straight line relationship with the product of duration of exposure and concentration as it is in the case of an asphyxiant like carbon monoxide. A single exposure to a high concentration of an irritant can have an intense effect and can terminate fatally. However, this acutely fatal exposure might be tolerated by the system if the concentration were halved as if it were inspired over a period of twice as long. This fact leads to the conclusion that any reduction in the concentration of an irritant during its passage throughout the upper respiratory tract results in a more proportionate sparing of the lung tissues.

Some Typical Examples of Gaseous Irritants

Highly soluble - Affecting mainly the upper respiratory tract:
ammonia
hydrogen chloride
sulfur trioxide
hydrogen fluoride
formaldehyde
acetic acid
acetic anhydride
sulfur monochloride
thionyl chloride
sulfuryl chloride

Intermediately soluble - Affecting the upper respiratory tract and deeper structures as the bronchi:
sulfur dioxide
chlorine
bromine
iodine
arsenic trichloride
phosphorus trichloride
phosphorus pentachloride

Least soluble - minimal primary irritations; causes delayed pneumonitis:
ozone
nitrogen dioxide
phosgene

No general rule as to the local of action:
acrolein
ethyl chlorosulfonate
dimethyl sulfate
dichloromethyl ether
dichloroethyl sulfide (mustard gas)
methyl chlorosulfonate
chloropicrin
xylyl bromide

PRECAUTIONS

1. Precautions to prevent inhalation of the gases should be employed to include adequate ventilation and approved respirators. The availability of adequate approved and well maintained respirators is essential in many situations to prevent the loss of life due to emergency releases.

2. Adequate personal protective equipment should be used to include safety goggles, face shields as warranted, gloves and protective aprons.

3. An approved safety shower and eye wash device capable of providing a sufficient quantity of tempered water to flush the skin and eyes for a period of a minimum of 15 minutes should be provided.

4. All precautions as applicable for handling compressed cylinders must be employed when working with pressurized materials.

5. Emergency response procedures should be well understood by all individuals involved in use of corrosives gases.

Note that the hazard level of some of these chemicals may be well below their odor level!

CONCLUSION

The control of corrosives-irritants must include proper protective equipment, proper emergency response training, properly designed and maintained ventilation equipment and periodic exposure surveys. When irritants are used, careful study must be made to evaluate the problem and to design control equipment.

In addition to control of process exposure, provisions must be made to protect all persons during unusual conditions as spills or explosions. This requires thorough safety training in the proper use of respirators and other protective equipment. It is imperative that all persons be trained in proper first aid practices and evacuation techniques.

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XIX. SUBSTANCES THAT PRESENT A HAZARD DUE TO ACUTE OR CHRONIC TOXICITY

Recommendations for handling procedures for toxic chemicals begin with the admonition that, even for substances of no known significant hazard, it is prudent to observe good laboratory practice, minimizing exposure working in an exhaust hood, wearing eye and hand protection and a laboratory coat or apron. Classification of chemicals as to exact degree of hazard is difficult due to many variables involved and the difference of definition of toxicity. However, a number of organizations have formulated guides which rate commonly used chemicals as to toxicity. One of the most widely used guides is that formulated by the National Fire Protection Association (NFPA).

The NFPA system rates chemicals as to hazard on a numerical scale range from 0 - 4. The description of the hazard characteristics of the different categories are as follows:

4 -Materials too dangerous to health to expose fire fighters. A few whiffs of the vapor could cause death or the vapor or liquid could be fatal on penetrating the fire fighter's normal full protective clothing which is designed for resistance to heat. The normal full clothing and breathing apparatus available to the average fire department will not provide adequate protection against inhalation or skin contact with these materials.

3 -Materials extremely hazardous to health but areas may be entered with maximum care. Full protective clothing, self- contained breathing apparatus, rubber gloves, boots and bands around the legs, arms and waist should be provided. No skin surface should be exposed.

2 -Materials hazardous to health but areas may be entered freely with self-contained breathing apparatus.

1 -Materials only slightly hazardous to health and where canister- type masks may be used.

0 -Materials which on exposure under fire conditions would offer no hazard beyond that of ordinary combustible material.

The guide should not be used exclusively as a measure of the toxicity of a particular material but can be relied upon as a preliminary impression of the hazard of the substance. All available resources should be consulted by those using a chemical to develop as good an understanding of its toxicity as possible. The importance of a knowledge of the toxic characteristics of chemicals one will be working with can not be overstated.

Procedures for Working with Substances of Moderate Chronic or High Acute Toxicity

1. Learn and obey all applicable general laboratory safety procedures.

2. Protect the hands and forearms by wearing either gloves and a laboratory coat or suitable long gloves to avoid contact of toxic material with the skin.

3. Procedures involving volatile toxic substances and those involving solid or liquid substances that may result in the generation of aerosols should be conducted in a hood or other suitable containment device.

4. Practice good personal hygiene, particularly the thorough and frequent washing of the hands and arms.

Additional Procedures for Handling of Substances of Known High Chronic Toxicity

1. Each laboratory worker's plan for experimental work and for disposing of waste materials should be approved by the work area supervisor (faculty member of the research group).

2. Consultation with the Department Chemical Hygiene Officer should be made to insure that adequate provisions are being followed.

3. An accurate record of the amounts of substances being stored and the amounts used, dates of use and names of users should be maintained.

4. A record of disposal of substances should be maintained.

5. Any volatile substance having high chronic toxicity should be stored in a well ventilated storage area within a secondary container having sufficient capacity to contain the material should the primary container accidentally break.

6. All containers should be labeled to identify the contents and include a warning such as - "WARNING - HIGH CHRONIC TOXICITY" or "WARNING - CARCINOGENIC AGENT".

7. Storage areas should have limited access to authorized personnel only and special signs should be posted warning those not aware of the presence of the material.

8. All experiments should be performed in controlled areas. A controlled area may consist of an entire room, a set-aside portion of a room or a specified device such as an exhaust hood or glove box. The magnitude of the controlled area is related to the characteristics of the particular material and the situation of usage.

9. Exhaust air from experiments using highly toxic substances should be properly decontaminated before released to the ambient air. Decontamination can be performed by scrubbers, activated charcoal devices, HEPA filters, etc.

10. Exhaust from laboratory vacuum pumps used with substances having high chronic toxicity should be treated and vented into an exhaust hood. Appropriate precautions must be applied to decontamination of pumps and pump oil.

11. Surfaces on which chronic toxicity substances are handled should be protected from contamination by using chemically resistant trays or pans that can be decontaminated after the experiment or by using dry, absorbent, plastic-backed paper that can be disposed of after use.

12. All waste material must be properly labeled, stored, transported and approved disposal must be arranged.

13. Regulated areas in which the toxic materials are being used should be maintained at a lower atmospheric pressure than the surrounding non-regulated areas.

14. Suitable medical monitoring personnel should be provided. The specific evaluations to be performed should be determined by review of the pertinent characteristics of the agent(s) being handled.

Some Examples of Substances Considered as High Chronic Toxicity

1. Certain heavy metal compounds including methyl mercury and nickel carbonyl.

2. Carcinogens to include:
2-Acetylaminofluorene
Acrylonitrile
4-Aminobiphenyl
Asbestos
Bis(chloromethyl)ether
3,3'-Dichlorobenzidine (and its salts)
4-Dimethylaminoazobenzene
Ethylenimine
Inorganic arsenic
Methyl chloromethyl ether
4,4'-Methylene-bis(2-chloroaniline)
alpha-Naphthylamine
beta-Naphthylamine
4-Nitrobiphenyl
Nitrosodimethylamine
beta-Propiolactone
Vinyl chloride
Benzo[a]pyrene
3-Methylcholanthrene
7,12-Dimethylbenz[a]anthracene
Hexamethylphosphoramide
2-Nitronaphthalene
Numerous N-Nitrosamines
Aflatoxin B1
2-Acetylaminofluorene

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XX. HAZARDS OF CRYOGENIC SUBSTANCES

The primary hazard of cryogenic materials is their extreme coldness. They, and the surfaces they cool, can cause severe burns if allowed to contact the skin. Other hazards associated with cryogenics include flammability of substances such as liquid hydrogen, methane, ethylene, etc., pressures generated in the expansion process from the liquid to gas phase and the material deterioration effect of the cold substance.

PRECAUTIONS

The following precautions should be applied to the handling of cryogenic substances:

1. Personnel should be thoroughly trained in the nature of the hazards, precautions necessary to control exposure hazards and emergency procedures.

2. Equipment should be kept scrupulously clean to avoid hazardous conditions on contact with cryogenic fluids, especially oxygen.

3. Mixture of gases or fluids should be strictly controlled to prevent formation of flammable or explosive mixtures.

4. When flammable gases are in use, potential ignition sources should be eliminated. Work areas, rooms, chambers and laboratories should be monitored continuously to automatically provide a warning of the build-up of flammable vapors.

5. Where the possibility of bodily contact with cryogenic material exist, full face protection, impervious apron or coat, cuffless trousers and high-topped shoes must be worn. Watches, rings, bracelets and other jewelry should be removed before entering cryogenic areas. Gloves should be worn, but they should be impervious and loose fitting to permit quick discard in case of a splash or spill.

6. When toxic gases are being used, suitable respiratory protective equipment should be readily available to all personnel. Since extremely high concentrations of cryogenic gas can be suddenly encountered, these masks should be of the positive pressure air supplied type. Canister masks are not suitable for this service. This precaution is especially important for the asphyxiant gases such as nitrogen.

7. Storage of cryogenic fluids must be in well insulated containers to minimize loss of the liquified gas by boil-off. The containers should be loosely stoppered and provisions provided to prevent plugging due to accumulation of ice from the ambient atmosphere. Storage should include efficient ventilation to prevent accumulation of dangerous vapor concentrations.

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XXI. HAZARDS OF WATER REACTIVE CHEMICALS

There are a number of chemicals used in laboratory procedures which react violently with water. The danger associated with these chemicals frequently comes from the formation of potentially explosive or flammable gases. With other substances, the hazard is due to the spontaneous ignition or explosion of the material itself. Extreme caution should be exercised when handling water reactive chemicals.

Some Water Reactive Chemicals

Alkali Metals
Potassium metal (K)
Sodium (Na)
Lithium (Li)
Cesium (Cs)

Alkali Metal Hydrides
Lithium aluminum hydride (LiAlH4)
Sodium borohydride (NaBH4)
Sodium hydride (NaH)
Potassium hydride (KH)
Calcium hydride (CaH2)

Alkali Metal Amides
Silver amide (Ag2NH)
Cuprous nitride (Cu3N)
Cadmium amide (Cd(NH2)2)
Lead amide (PbNH)
Sodium amide (NaNH2)
Potassium amide (KNH2)
(Note: The latter two chemicals under certain conditions)

Metal Alkyls
Alkyllithiums
Aryllithiums
Trialkylaluminums

Halides of Non-Metals
Boron trichloride (BCl3)
Boron trifluoride (BF3)
Phosphorus trichloride (PCl3)
Phosphorus pentachloride (PCl5)
Silicon tetrachloride (SiCl4)
Sulfur monochloride (S2Cl2)

Inorganic Acid Halides
Phosphorus oxychloride (OPCl3)
Sulfur chloride (S2Cl2)

Anhydrous Metal Halides
Aluminum chloride anhydrous (AlCl3)
Titanium tetrachloride (TiCl4)
Zirconium tetrachloride (ZrCl4)
Stannic chloride (SnCl4)

Others
Phosphorus pentoxide (P2O5)
Calcium carbide (CaC2)
Organic acid halides and
hydrides of low molecular weight

PRECAUTIONS

1. Containers of water reactive chemicals must be protected from physical damage. Containers should be kept tightly sealed during storage.

2. A thorough evaluation of the procedures of storage and handling should be periodically performed to insure that adequate separation from all sources of water has been insured.

3. Areas containing water reactive chemicals should be posted so that fire department personnel and others are aware of the presence of the materials.

4. Electrical equipment located in areas where larger quantities of the chemicals are stored should be of an approved, explosive-proof type.

5. Wear appropriate personal protective equipment when handling the chemicals to include chemical goggles, face shields as warranted, gloves, aprons, etc.

6. Sources of ignition to include smoking must be controlled in storage and handling areas.

7. Separation from incompatible chemicals such as organic metals, other combustibles, chlorinated hydrocarbons, etc., must be maintained.

8. Store those chemicals, such as lithium and sodium, that are prescribed to be maintained submerged in Kerosene or other inert oils, as indicated.

9. Clean up all spills immediately and properly dispose of the residue.

10. Make sure that the appropriate class of fire extinguisher is available where materials are stored or handled.

Classification of Portable Fire Extinguishers

Class A: Ordinary combustibles such as wood, cloth, paper, etc.

Class BC: Flammable liquids and energized electrical equipment

Class ABC: Multipurpose for Classes A, B and C

Class D: Flammable metals such as sodium, lithium, magnesium, etc.

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XXII. HAZARDS OF PYROPHORIC (AIR REACTIVE) CHEMICALS

Pyrophoric chemicals are those that react violently on exposure to air leading to spontaneous ignition. Extreme caution should be exercised when handling pyrophoric chemicals.

1. Containers must be air-tight and protected from physical damage.

2. Chemicals must be stored under water or in an inert atmosphere.

3. All handling procedures must be performed in an inert atmosphere.

4. Wear appropriate personal protective equipment to include chemical goggles, face shields as warranted, gloves, aprons, etc.

5. Avoid contact with incompatible materials.

6. Areas containing air reactives should be posted to alert emergency response and other authorized personnel.

Some Pyrophoric (Air Reactive) Chemicals

Grignard Reagents
(RMgX)

Metal Hydrides
Sodium hydride (NaH)
Lithium aluminum hydride (LiAlH4)

Metal Alkyls and Aryls
(RLi)
(RNa)
(R3Al)
(R2Zn)

Non-Metal Hydrides
Diborane (B2H6)
Phosphine (PH3)
Arsine (AsH3)
Other boranes

Metal Carbonyls
Nickel tetracarbonyl (Ni(CO)4)
Iron Pentacarbonyl (Fe(CO)5)
Cobalt carbonyl (Co2(CO)8)

Non-Metal Alkyls
(R3B)
(R3P)
(R3As)

Alkali Metals
Sodium (Na)
Potassium (K)

Metal Powders (Particularly when finely divided)
Aluminum (Al)
Cobalt (Co)
Iron (Fe)
Magnesium (Mg)
Palladium (Pd)
Platinum (Pt)
Tin (Sn)
Zinc (Zn)
Zirconium (Zr)
Others
White Phosphorus

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End of University of Tennessee Chemical Hygiene Plan. Copyright 1994, 2003 by the Department of Chemistry, University of Tennessee, for this page and all linked pages.
Please email Prof. Brian Long long@utk.edu (Chemical Hygiene Officer) for permission to copy.


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