Introduction

Hazardous chemicals may be grouped as follows:

Caustic or Corrosive: Acids and alkalis may cause burns of the skin, mouth, lungs, or eyes and irreversible damage to equipment and storage areas.

Toxic Chemicals: Almost any substance in sufficient quantity can be considered toxic. Toxic chemicals are those which damage biological structure and function through exposure or accumulation in tissues. Usually, this involves relatively small amounts of the toxin.

For these purposes, a poison will be defined as a substance which may cause death or serious health effects if relatively small amounts are inhaled, ingested or absorbed by the skin. Poisons may be gas, liquid or solid.

Carcinogens: Substances designated by the Occupational Safety and Health Administration (29 CFR Part 1910, Sub-part Z) as being a carcinogen require special handling.

Specific authoritative sources such as the Registry of Toxic Effects of Chemical Substances (RTECS), the National Toxicology Program (NTP) Annual Report on Carcinogens, and the International Agency for Research on Cancer (IARC) monographs serve as primary sources of toxic chemical information.

Flammables: Materials that may easily ignite, burn and serve as fuel for a fire.

Reactives: Materials that may release large amounts of energy under special circumstances.

A. Caustics and Corrosives

Contact with the skin or eyes represents the greatest risk when dealing with corrosives. Match the hazard presented by the material with which you are working with the protective equipment recommended by the MSDS. Always wear resistant gloves and eye protection when dealing with corrosives. In some cases, respiratory protection may be desirable (contact the Environmental Health & Safety Office for information on the respiratory protection plan).

1. Handling

• Be aware of the nearest eyewash station and safety shower for your work location.
• When acids or alkalis are used some form of containment to control spills must be employed. Included among these methods are bench top spill diapers and resistant trays.
• Do not pipette by mouth. Use a mechanical or vacuum-assisted pipette aid.
• When diluting, always add ACID to WATER, never add water to acid. Allow the acid to run down the inside of the container and mix slowly by gentle rotation.
• Be aware of the methods, materials and procedure for cleaning corrosive spills. In the event of a spill beyond your immediate ability to control, notify the Environmental Health and Safety Office (Dial-6342).

• Store corrosives in a cool, dry and well ventilated area away from direct sunlight.
• Use storage materials which are resistant to corrosion.
• Store caustic and corrosive materials near the floor to minimize danger of bottles falling from shelves.
• Large amounts of corrosive chemicals require a dedicated corrosive storage cabinet.
• Segregate acids from bases. Store chemicals according to their primary hazard classification.
• Acid bottle carriers must be used for containers over one quart in size.

1. organics
2. flammables
3. toxic materials

3. General First Aid Considerations for Corrosives

In the event that a corrosive contacts the skin, immediately remove any contaminated clothing and flush the area with copious amounts of water. Use care not to rub or damage the skin. Notify your supervisor and seek medical attention.

In the event that a corrosive chemical contacts the eyes, immediately flush the eyes with large amounts of clean water, including under the eyelids for at least 15 minutes. Seek immediate medical attention.

If a corrosive material is ingested, DO NOT induce vomiting. Seek immediate medical attention.

B. Toxic Chemicals

1. Handling and Storage

• Isolate, segregate, and clearly label all toxic chemicals. See Appendix D Acutely Toxic Gases and Chemicals
• Adequate room ventilation must be provided at the work site area. A fume hood must be used whenever possible.
• The appropriate personal protective equipment must be worn as directed by the label or MSDS. If in doubt, contact the Chemical Hygiene Officer.
• Limit exposure time.
• Practice good personal hygiene.
  • -- hand washing
  • -- wearing a lab coat

Special consideration must be given to this poison which is used in many laboratories at the College.

Use care to avoid spills of elemental mercury.

CLEAN UP SMALL GROSS spills with a pipette or "Sweeper." Ventilate area well to remove mercury vapors. Large spills (>1 ml) should be referred to the Environmental Health & Safety Office. (Dial-6342)

Chronic exposure and absorption of mercury may lead to a metallic taste in mouth, a gray line around gums and neurological problems.

Do not place elemental mercury waste in drains. Contact Chemical Hygiene Officer for proper disposal.

Due to its toxicity and difficulty of disposal, the purchase of mercury and mercury containing items is strongly discouraged. For items such as thermometers, red liquid should be substituted.

C. Carcinogens

Carcinogens (see Appendix G, Select List of Carcinogens) are hazardous chemicals capable of increasing the risk of cancer(s) through exposure, usually over time. Teratogens are hazardous chemicals capable of causing an increased risk of birth defects in children of exposed workers.

Prudent practices need to be used in dealing with known or suspected carcinogens and teratogens. Reduce your exposure to these chemicals to the lowest possible level through good work habits and common sense.

The greatest potential harm is a result of repeated or prolonged exposure to these chemicals in excess of the acceptable limits.

Other behaviors such as diet and smoking can contribute to the synergistic or antagonistic effects of carcinogenic materials.

Plan ahead for problems with carcinogenic compounds. A protocol should exist for handling, storing, disposal and emergency procedures to be followed.

D. Flammables

• Combustible
• Combustible Liquid
• Flammable Aerosol
• Flammable Gas
• Flammable Liquid
• Flammable Solid

Because flammable and combustible materials are widely used in laboratory operations, the following rules should be observed:

• When a flammable liquid is withdrawn from a drum, or when a drum is filled, both the drum and other equipment must be electrically bonded and grounded.
• Keep only minimum quantities of flammable liquids (including solvents) in the laboratory. Quantities greater than 1 gallon must be stored in approved safety containers. Maintain storage for current work only.
• Keep flammable liquids away from heat and direct sunlight.
• DO NOT heat flammable liquids directly over a burner or an electrical device which may generate sparks.
• Flammable liquids must not be located in the laboratory so that they block aisles or exits.
• Flammable liquids must be stored in locations such that accidental contact with strong oxidizing agents such as chromic acid, permanganates, chlorates, or perchlorates is not Possible.
• A fume hood should be used when appreciable quantities of flammable materials are transferred from one container to another, allowed to stand in open containers, or heated in open containers.
• Do not use an open flame to heat a flammable liquid or to carry out a distillation under reduced pressure.
• Before lighting a flame, remove all flammable substances from the immediate area.
• Check all containers of flammable materials in the area to ensure that they are tightly closed.
• Notify other occupants of the laboratory in advance of lighting a flame.
• Store flammable materials properly.
• When volatile flammable materials may be present, use only non-sparking electrical equipment.
• Use solvents at temperatures 10 to 15 degrees below their flashpoint, if possible.
• Note the location and type of fire fighting equipment available for the particular need. Flammable liquid fires are Class B fires. Extinguishers that are effective on class A,B,& C fires are available throughout the College.
• Remember that flammable liquids may have other health consequences as well. Prudent practices need to be observed in storing and disposing of flammable liquids.
• Quantities of more than one gallon must be stored in a safety can. If a reagent must be stored in glass for purity, the glass container should be placed in a bottle carrier to lessen the danger of breakage.
• Small quantities (working amounts) may be stored on open shelves, but bulk storage (more than one gallon) must be in a designated flammable storage area or flammable material cabinets.

Refrigeration and Cooling Equipment

The use of domestic refrigerators for the storage of solvents presents a significant hazard to the laboratory work area. This practice is prohibited.

Only FM or UL approved "explosion-proof" or "laboratory safe" refrigeration equipment may be used for flammable materials. Explosion-proof refrigeration equipment is designed to protect against ignition of flammable vapors both inside and outside the refrigeration compartment. "Laboratory Safe" provides protection only on the inside.

Every laboratory refrigerator must be clearly labeled to indicate whether or not it is acceptable for storage of a flammable material. The required labels are available through the Chemical Hygiene Officer.

F. Reactives

Reactive chemicals are characterized by their tendency to release large amounts of energy under certain conditions. Since the catalyst for these reactions frequently is found in the normal environment, special precautions need to be observed to safely use and store these materials. Included in this category are explosives, water reactive materials, air sensitive materials, and mixtures of oxidizing and reducing agents.

1. Handling and Storage

• Know the specific properties of the materials prior to initiating the work.
• Ensure adequate protection against shock, extremes in temperature, other reactive chemicals, and potential sources of ignition.
• Segregate oxidizers from reducers. Store reactive chemicals according to their primary hazard classification.
• Isolate reactive chemicals from toxic materials and flammables.
• Use adequate personal protective equipment. Many reactive chemicals liberate toxic fumes or gases. Small, easily managed amounts must be used in a ducted fume hood.

Return to the Chemical Hygiene Plan Index.