Section E:  Provisions for Particularly Hazardous Materials

1.  Chemicals of Chronic or High Acute Toxicity

Definitions:

• Carcinogen: Substances that are suspected or known to cause cancer.  Some have threshold limits of exposure. A list of carcinogenic chemicals can be found in Appendix G.
• Mutagen:  Chemical or physical agent that causes genetic alterations
• Teratogen:  Substances that cause the production of physical defects in a developing fetus or embryo.
• Substances with a High Acute Toxicity: Any chemical falling within any of the following OSHA defined categories:
1. A chemical that has a LD₅₀ of 50 mg/kg or less when administered orally to a test population.
2. A chemical that has a LD₅₀ of 200 mg/kg or less when administered by continuous contact for 24 hours to a test population.
3. A chemical that has a LC₅₀ in air of 200 ppm or less of a gas or vapor, or 2 mg/L or less of mist, fume, or dust when administered by continuous inhalation for one hour to a test population.

General Guidelines

• As a general rule, carcinogen and chemicals of high acute toxicity will not be used unless no suitable alternative is available. Approval from the safety committee must be obtained before ordering any carcinogen or chemical of high acute toxicity.
• Prepare a plan for the use and disposal of these materials before beginning any laboratory work.
• Be prepared for accidents and spills. Know the location of all safety equipment. Have the appropriate clean up equipment on hand. The appropriate clean up supplies can be determined by consulting the material safety data sheet.
• The proper personal protective equipment including gloves, ensure gloves are impervious to the chemical being used, and a long sleeved lab coat must be worn.

Storage Guidelines

• Chemicals of chronic or high acute toxicity shall be stored in a cool dry location with warning signs and adequate ventilation.
• Chemicals of chronic or high acute toxicity can be stored in a laboratory if a designated area is set up and properly labeled as such.
• Containers of prepared solutions that contain a chemical of chronic or high acute toxicity must be stored in a secondary container large enough to contain a spill.
• All containers must be clearly labeled (Labeling Procedures) and must include the appropriate health hazards.

Handling Guidelines

• All work should be performed in a fume hood. The area in which the research is being carried out must be clearly marked with warning signs if left unattended, such as "Warning: Highly Toxic Substance in Use".
• If a chemical of chronic or high acute toxicity is transferred to a secondary container, the container must be properly labeled with the name of the chemical (chemical formulas and structural formulas are not acceptable), date, your supervisors name, and the health hazard.
• Never leave a container of chemical of chronic or high acute toxicity opened or unlabeled.
• Clean up small spills thoroughly.
• If a spill occurs outside the fume hood, evacuate the area and notify your instructor or the chemical hygiene coordinator.
• When you are finished working, clean all areas where the chemical was used.
• All empty containers that contained a chemical of chronic or high acute toxicity, including the original manufacturer bottle, must be washed with water twice with the washings being treated as waste.
• Remove all protective equipment before leaving the lab. Wash your hands and any other exposed body surface thoroughly.

2.  Compressed Gases

Definition: 

A compressed gas is any material or mixture having in the container an absolute pressure exceeding 40 psia at 21 ^oC (70 ^oF), or a pressure exceeding 104 psia at 54 ^oC (130 ^oF), or any flammable liquid material having a vapor pressure exceeding 40 psia at 38 ^oC (100 ^oF).

General Guidelines

• Compressed gas cylinders should be handled as high-energy sources and therefore as potential explosives.
• All cylinders, full and empty, must be restrained.
• Before using a compressed gas, be familiar with the properties of the gas.
• Always wear your safety goggles when handling compressed gases.
• Do not extinguish a flame involving a highly combustible gas until the source of gas has been shut off.
• If you are using a compressed gas that is not listed below, you must consult the chemical hygiene coordinator so that the proper procedures for that gas can be added to the chemical hygiene plan.
• Gas cylinders can only be ordered from companies that will accept the return of empties.
• Whenever possible, lecture bottles must be ordered from companies that accept the return of partially filled or empty cylinders.
• The contents of any compressed gas cylinder must be clearly identified by the manufacturer. Any cylinder that is not clearly identified will not be accepted and will be returned to the manufacturer. Color-coding is not a reliable means of identification.
• Paper tags will be used on all cylinders to indicate the state of the tank as: Full, In Service, or Empty.
• Contents of the cylinder must be visibly labeled including hazard class. To ensure that the name of the gas and hazard class are easy to see when a regulator is installed, the user of the gas will attach a tag indicating the name of the gas, that the cylinder is "In Service" and the appropriate hazard class as indicated below:
  

Compressed Gas	Must be labeled as
Acetylene	Flammable Gas
Argon	Non-Flammable Gas
Helium	Non-Flammable Gas
Hydrogen	Flammable Gas
Nitrogen	Non-Flammable Gas
Nitrous Oxide	Non-Flammable Gas
Oxygen	Oxygen Containing Gas

Storage Guidelines

• When a new cylinder is received:

o It must be immediately inspected to insure it is not leaking, that the proper cap is securely in place, and that it is properly labeled.

o A status tag indicating that the cylinder is full must be secularly attached to the cylinder. The date the cylinder was received should be added to the top of the status tag.

o All extra gas cylinders will be located in the chemical storage building. They must be secured at all times. Valves are to remain closed and caps are securely in place when not in use.

o Oxygen cylinders cannot be stored in the same vicinity as flammable gases. Therefore, DO NOT store flammable gases in the compressed gas storage room in chemical storage building.

o Empty cylinders must be identified as emptied and returned to the chemical storage building and separated from full cylinders.

Handling Guidelines

• In use cylinders must be secured at all times to prevent tipping, falling, or rolling. They must be securely attached to walls, benches, or other fixed surface with chains or straps.
• Be sure the cylinder has a hazard class tag, is labeled as ″In Service″, and the name of the gas can be easily seen. If the manufacturer label is against the wall, write the name of the gas on the hazard class tag.
• Regulators are gas specific and not necessarily interchangeable. Always make sure you are using the proper regulator.
• Check for leaks with soapy water.
• Cylinder valves should be opened slowly and only after the proper regulator has been attached.
• Never use any kind of lubricant on valve regulators.
• There shall be no smoking or open flames in areas were flammable compressed gases are being stored or used.
• Be aware that rapid release of a compressed gas will cause an unsecured gas hose to dangerously whip around.
• Do not extinguish a flame involving a highly combustible gas until the source of the gas has been shut off.
• Rapid release of a compressed gas builds up a static charge that could ignite the gas if it is flammable or combustible.
• Never bleed cylinders completely. Leave a slight pressure (25 psi) to keep out contaminants.
• Acetylene cylinders:

o Always store acetylene cylinders upright.

o Do not use an acetylene cylinder that has been stored or handled in a non-upright position until it has sat for in an upright position for at least 30 minutes.

o Ensure that the outlet line of an acetylene cylinder is protected with a flash arrester.

o Never exceed the pressure limit indicated by the warning red band of an acetylene pressure gauge.

o Ensure that the tubing being used for transporting acetylene gas is appropriate. Some tubing materials such as copper form explosive acetylides.

Transportation of Compressed Gas Cylinders

• Use only the gas cylinder cart, properly designed for moving gas cylinders, when moving a cylinder.
• Do not drag, roll or slide cylinders.
• Secularly strap the cylinder to the cart.
• The valve should be closed and the cover cap secured in place before moving the cylinder. Do not move a cylinder with a regulator.
• Handle only one cylinder at a time.
• Do not ride the elevator with a compressed gas cylinder.
• Students are not allowed to transport compressed gas cylinders by themselves. They must be properly trained and must be accompanied by a faculty/staff employee.

Lecture Bottles

• Whenever possible, lecture bottles must be ordered from companies that accept the return of partially filled or empty cylinders.
• Use only in a chemical hood.
• Lecture bottles must be secured
• Regulators are gas specific and are not necessarily interchangeable. Always make sure you are using the proper regulator. Name all associated equipment with the gas name to prevent unintentional mixing.
• Lecture bottles must be inspected twice a year for signs of leakage and/or corrosion. If the bottle shows signs of leakage and/or corrosion, the bottle must be returned to the supplier or special arrangements must be made for disposal.

3.  Corrosive Chemicals

Definition- The definition of corrosive chemicals is very broad. In general terms a corrosive chemical can be defined as a chemical where living tissue as well as equipment is destroyed on contact. Strong acids and bases, dehydrating agents, and oxidizing agents are commonly considered corrosive chemicals. A list of common corrosive chemicals is found in Appendix H.

General Guidelines

• The following is a list of the major classes of corrosive chemicals.

Concentrated Acids	Concentrated acids can easily attack skin and eyes causing severe and painful burns. Hydrofluoric acid is an extremely dangerous material and all forms, including vapors and solutions, can cause severe, slow-healing and painful burns.
Concentrated Bases	Alkali metal hydroxides are very destructive to the skin and particularly to the eyes.
Dehydrating Agents	Dehydrating agents have a strong affinity for water. When they are added to water too rapidly, a violent reaction accompanied by spattering can occur. These substances can cause severe burns on contact with the skin or eyes.
Oxidizing Agents	Powerful oxidizing agents are considered corrosive chemicals. The halogens are strong oxidizing agents and because they are gases they pose danger to sensitive tissues through inhalation.

Storage Guidelines

• Large quantities of inorganic corrosives will be stored in acid room of the chemical storage building in a clearly labeled area.
• In an effort to reduce the transport of concentrated acids and bases to the 2^nd and 3^rd floors, large quantities (2.5-L bottles) of concentrated acids and bases will not be stored on the 2^nd or 3^rd floors whenever practical and will be replaced with smaller working quantities. If you need a 2.5 L bottle of concentrated acid, notify the laboratory chemist.
• Large quantities of organic corrosives will be stored in a separate area of the organic storeroom and clearly labeled as such.
• Smaller working quantities of concentrated acids should be stored in corrosive cabinets.
• Storage areas must be kept dry, well ventilated and cool, but not cold as acetic acid freezes at 60 ^oF (16 ^oC)
• Isolate corrosives from all other nearby chemicals.
• Whenever possible, store corrosives in their original shipping containers.
• Acid spill control material must be readily available.
• Store corrosives four feet or less above the floor.
• Recognize that some acids, such as perchloric and fuming nitric, must be treated as strong oxidizers rather than acids.
• Separate corrosives that will react with other corrosives. Nitric acid should be stored by itself in an acid cabinet if possible.
• Perchloric acid cannot be used in Sims. Perchloric acid requires a special perchloric acid hood which is not available in Sims.

Handling Guidelines

• Eye protection, indirect or nonvented splash goggles, must always be used when handling corrosive materials. Nonvented splash goggles are the best protective eyewear to use when working with concentrated acids and bases.
• Chemical resistant rubber gloves, a face shield and a heavy-duty rubber apron may also be appropriate, such as when working with concentrated corrosives. Such personal equipment is not necessary when working with dilute acids and bases since washing with water is sufficient in decontaminating the skin.
• Never add water to acid. When diluting a concentrated acid, always add acid slowly and cautiously to water.
• Corrosive chemicals can only be used in areas that are equipped with an eyewash station and safety shower.
• In the event of skin or eye contact with a corrosive chemical, remove all affected clothing and immediately flush the area with cool water for 15 minutes. Seek medical help.
• Procedures involving concentrated corrosive chemicals or chemicals that may result in the generation of corrosive fumes, gases, vapors, aerosols and/or dusts must be conducted in a fume hood.
• Be prepared for spills. For large spills of corrosive chemicals, evacuation of the building maybe required.
• When strong corrosives are used in student experiments, the students must be informed on the nature of the corrosive and any precautions that must be followed.
• Perchloric acid is a powerful oxidizing agent. Most fume hoods are not suitable for the using perchloric acid. Sims is not equipped with a perchloric acid hood.
• Because dry picric acid is a highly explosive, picric acid should only be purchased if no suitable alternative is available. Before purchasing picric acid, permission form the chair must be obtained, and a thorough investigation into the hazards of picric acid must be completed. A maintenance schedule to ensure that picric acid does not dry out must be established.
• Dry picric acid is explosive. Any old container of picric acid that dried up must be disposed of only with expert assistance. Do not move the container.
• Hydrogen fluoride is very toxic both as a gas and in solution. Before purchasing hydrogen fluoride or hydrofluoric acid, permission form the chair must be obtained, and a thorough investigation into the hazards of hydrofluoric acid must be completed. Even contact with dilute solutions of hydrofluoric acid can result in a serious burn.

Transporting Guidelines

• Use caution when transporting corrosive chemicals:
• Use a nonbreakable, secured secondary container for transporting a corrosive chemicals or transport chemicals on a cart with sides that can contain a spill.
• Use the elevator when transporting corrosive chemicals between floors. Corrosive chemicals cannot be transported up and down the stairwells.

4.  Cryogenic Liquids

Definition- Liquefied gases that condense oxygen from the air create an oxygen rich atmosphere and increase the potential for fire if flammable or combustible materials and a source of ignition are present.

General Guidelines

• A number of hazards may be present from the use of cryogenic liquids. All employees and students should be properly trained in using such materials prior to use.
• Tissue damage, similar to a thermal burn, will result with even very brief contact with a cryogenic liquid including any surface cooled with the liquid.
• Always wear splash goggles when handling. Wearing a face shield is also recommended.
• Gloves should be impervious and sufficiently large to be readily thrown off should a cryogen spill.
• Watches, rings, and other jewelry should not be worn.
• All rooms were cryogenic liquids are used, must have an oxygen sensor.

Storage and Handling Guidelines

• Containers and systems containing cryogens should have pressure relief mechanisms.
• Containers and systems should be capable of withstanding extreme cold without becoming brittle. Do not transfer any cryogenic liquid into a nonapproved container. Transfer liquid nitrogen only into glass Dewar flask approved for cryogenic liquids.
• Adequate ventilation is required when using liquid nitrogen or helium. Oxygen can be condensed out of the atmosphere creating a potential explosive situation. Also, oxygen can be displaced from the atmosphere causing an oxygen deficiency resulting in asphyxiation.
• Never ride on the elevator when transporting a cryogenic liquid.

5.  Flammable and Combustible Liquids

Definitions:

• Flammable liquids- any liquid having a flashpoint* below 38 ^oC (100 ^oF).

• Combustible liquids- any liquid having a flashpoint at or above 38 ^oC (100 ^oF)

These liquids are further subdivided into three groups:

	Flashpoint	Boiling Point	Examples
Flammables
Class IA	< 22.8 ^oC (73 ^oF)	< 37.8 ^oC (100 ^oF)	acetaldehyde, ethyl ether, cyclohexane
Class IB	< 22.8 ^oC (73 ^oF)	³ 37.8 ^oC (100 ^oF)	acetone, benzene, toluene, ethanol
Class IC	>22.8 ^oC (73 ^oF)	< 37.8 ^oC (100 ^oF)	Xylene, butanol
Combustibles
Class II	> 37.8 ^oC (100 ^oF) &  < 60 ^oC (140 ^oF)		acetic acid
Class IIIA	> 60 ^oC (140 ^oF) &  < 93.3 ^oC (200 ^oF)		cyclohexanol, formic acid, nitrobenzene
Class IIIB	> 93.3 ^oC (100 ^oF)		formalin, picric acid

*The flashpoint is defined as the minimum temperature at which a liquid gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid.

Storage Guidelines

• Flammable chemicals should not be purchased in containers larger than four liters.
• Flammable chemicals stored in the laboratories should be stored in flammable storage cabinets and the quantity should be kept to a minimum.
• Flammables should not be stored in areas exposed to direct sun light.
• Appropriate fire extinguishers and/or sprinkler systems and spill control materials will be available in all areas where flammable chemicals are used and stored.
• All chemical storage rooms must have a raised area in the doorway to contain spills.
• Any flammable chemical that must be stored in the refrigerator or freezer must be stored in an explosion proof refrigerator/freezer.
• Keep containers of flammable substances tightly closed.

Handling Guidelines

• Large amounts of flammable chemicals should be used only in vented hoods and away from sources of ignition, which includes not only flames, but also electrical equipment, static electricity and, for some material even hot surfaces.
• Smaller working amounts of flammable chemicals should be used in vented hoods whenever possible and away from sources of ignition.
• Heat flammable substances in steam, water, oil, hot air baths or heating mantles only.

6.  Peroxide-Forming Chemicals

Definition- chemicals, which undergo autoxidation reactions (a reaction with oxygen in the air) to form peroxides, which can explode with impact, heat, friction, shock, sparks or light

• Peroxides and peroxide forming chemicals are among the most hazardous chemicals handled in the laboratory. Organic peroxides are particularly unstable and very sensitive to impact. Anyone using such chemicals should consider the following general information and should thoroughly research information regarding any specific chemical to be used.

Storage Guidelines

• Date all chemicals that are known peroxide formers upon receipt and upon opening.
• Store away from heat and light sources.
• Ensure containers of peroxide forming chemicals are tightly sealed after each use.
• Label such chemicals as known peroxide formers.
• Limit stock of such chemicals to a three-month supply.
• Keep the stocks of peroxide forming chemicals to a minimum. Potential peroxide formers will not be allowed to evaporate to dryness.
• Do not use metal storage containers to store peroxide forming chemicals.
• Check for peroxide formation every three months to a year depending on the chemical. See Appendix I.
• Do not open any container, which has solid forming around its lid.

Handling Guidelines

• Before distilling any known or suspected peroxide former, it must be checked for peroxides. Peroxide test stripes are located in the refrigerator in Sims 304, 308, and 107. If the solvent tests positive for peroxides, it must be disposed of immediately.
• When distilling peroxide forming chemicals, the distillation apparatus should be assembled in a hood and in such a way that it is possible to remove the heat source.
• Never return unused peroxide forming chemicals to the original storage container.
• Do not use metal spatulas when working with such chemicals.
• Follow the same handling procedures outlined for flammable chemicals.

7.  Water Reactive Chemicals

Definition- a material that when comes into contact with water becomes spontaneously flammable or gives off a flammable or toxic gas and presents a health hazard. Examples include alkali and alkaline earth metals (sodium, magnesium, etc.), anhydrous metal halides (aluminum bromide, etc.), anhydrous metal oxides (calcium oxide, etc.), nonmetal oxides (sulfur trioxide, etc.), nonmetal halide oxides (phosphoryl chloride, etc.), and organometallics.

Storage

• Chemicals must be stored in a dry area, such as a chemical storage cabinet.
• Should not be stored in the same area as other combustible materials.
• Water reactive chemicals should be clearly labeled as such.

Handling

• The utmost care must be taken to avoid the contact of such chemicals with water.
• When using such chemicals, one should thoroughly research information of their use.