EHS masthead EHS Home LBL Home EHS Home EHS masthead

Chemical Hygiene and Safety Plan
HAZARD CONTROLS  arrow image 
AND PROCEDURES  arrow image
AND EQUIPMENT  arrow image
APPENDICES  arrow image
Search the CHSP:
spacer image
EH&S Home
PUB 3000
LBNL A-Z Index
LBNL Search
LBNL Phone Book
Privacy & Security Notice
spacer image spacer image


Flammable and combustible chemicals include liquids such as organic solvents, oils, greases, tars, oil base paints, and lacquers, as well as flammable gases. Flammable gases are discussed in PUB-3000, Chapters 7, “Pressure Safety and Cryogenics” and Chapter 13, “Gases.” The emphasis of this section is on flammable and combustible liquids.

Flammable and combustible liquids are defined by their flash points. The flash point of a liquid is the minimum temperature at which it gives off sufficient vapor to form an ignitable mixture with the air near its surface or within its containment vessel.  A liquid’s flash point is a function of its vapor pressure and boiling point.  Generally, the higher the vapor pressure and the lower the boiling point of a liquid, the lower its flash point will be.  The lower the flash point, the greater the fire and explosion hazard

Flammable and combustible liquids are classified by the National Fire Protection Association (NFPA) based on their flash points:

Flammable Liquids (Class I):  Liquids with flash points below 100°F (37.8°C) and vapor pressures not exceeding 40 pounds per square inch (absolute) at 100°F (37.8°C).  Flammable Class I liquids are subdivided as follows:

  • Class IA: Liquids having flash points below 73°F (22.8°C) and boiling points below 100°F (37.8°C). Flammable aerosols (spray cans) are included in Class IA.
  • Class IB:  Liquids having flash points below 73°F (22.8°C) and having boiling points at or above 100°F (37.8°C).
  • Class IC:  Liquids having flash points at or above 73°F (22.8°C) and below 100°F (37.8°C).  The boiling point is not considered.

Combustible Liquids (Classes II and III):  Liquids having flash points at or above 100°F (37.8°C).  Combustible liquids in Classes II and III are subdivided as follows:

  • Class II:  Liquids having flash points at or above 100°F (37.8°C) and below 140°F (60.0°C).
  • Class IIIA:  Liquids having flash points at or above 140°F (60.0°C) and below 200°F (93.4°C).
  • Class IIIB:  Liquids having flash points at or above 200°F (93.4°C).

Control Measures

Training and Information

  • Employees who either handle or who may be exposed to flammable and combustible liquids are required to complete Chemical Hygiene and Safety Training, EHS 348 (or 345 for Facilities personnel or 352 for summer students). 
  • All employees in the work area must be trained in the specific hazards and controls of the materials being handled. Area-specific training is a line management responsibility.  EH&S Industrial Hygienists are available to provide assistance.
  • flag image Consult the section entitled: Labels, for labeling requirements for primary and secondary containers. flag image
  • The entrance to the work area should be posted with a Caution Placard depicting hazards and emergency contact information.

Substitution and Chemical Inventory Management

  • Identify and use safer chemical alternatives (e.g., materials with higher flashpoints and higher boiling points) if possible.
  • If a safer chemical can’t be used then limit what you buy or borrow what you need from a colleague in your group or contact the Chemical Management System coordinator to assist you in finding a source of the chemical at LBNL.
  • Conduct periodic cleanouts to prevent accumulating unneeded chemicals.
  • Procure and use the minimum amount of material required for the operation, or
  • Keep working quantities of chemicals to a minimum. Don’t stockpile chemicals. 
  • Enter these materials into the Chemical Management System (CMS).


  • A fume hood or other appropriate exhaust ventilation system should be used when handling flammable and combustible liquids in a manner that may produce an airborne hazard (such as fumes, gases, vapors, and mists).  This includes procedures such as transfer operations, preparation of mixtures, blending, sonification, spraying, heating, and distilling.

Work Practices

  • Control all ignition sources when handling flammable and combustible liquids. 
  • Electrically bond and ground containers when transferring Class I flammable liquids and other flammable and combustible liquids at temperatures above their flashpoints.
  • Storing and consumption of food is permitted in designated areas only.  See Work Practice Controls for additional information.
  • Use a mechanical aid or a pipette bulb for pipetting.
  • Open bottles or carboys slowly and carefully and wear protective equipment to guard hands, face, and body from splashes and vapors/gases.
  • Wipe drips/residues from containers and work surfaces. 
  • Wash hands before leaving the work area and prior to consuming food/beverages.

Personal Protective Equipment (PPE):

Skin and eye contact shall be prevented. The following PPE should be worn when handling these materials.  Additional information may be found in the Personal Protective Equipment Section:

  • At a minimum, safety glasses with side shields, laboratory coats (coveralls are acceptable in shop settings) and closed-toe shoes will be worn when handling these materials. This is to be considered as minimum protection and must be upgraded if necessary.
  • Additional PPE such as chemical goggles, face shields, chemical aprons, disposable coveralls, chemically resistant gloves and respiratory protection must be worn if there is a greater chance of chemical exposure. An EH&S Industrial Hygienist may be contacted for assistance in selecting appropriate gloves and respiratory protection. The use of respiratory protection requires an industrial hygiene hazard evaluation and a medical clearance followed by a fit test and training by the Industrial Hygiene Group.
  • Consult “Eye and Face Protection” in the Personal Protective Equipment Section for guidance on the selection, uses, and limitations of safety glasses, chemical goggles, and face shields.
  • Since many chemicals are skin-absorbers (i.e. agents that readily pass through the skin) it is important to select gloves that are chemically resistant to the material.  Consult the PPE section.  This contains a list of skin-absorbing agents and provides detailed guidance for selecting chemically resistant gloves.
  • Gloves must be selected on the basis of their chemical resistance to the material(s) being handled, their suitability for the procedures being conducted, and their resistance to wear as well as temperature extremes. Improper selection may result in glove degradation, permeation of the chemical through the glove and ultimately personal exposure to the chemical.  This is a potentially serious situation.  Consult “Gloves” in the Personal Protective Equipment Section for guidance on the selection, uses, limitations, and disposal of chemically resistant gloves.   An EH&S Industrial Hygienist may also be contacted for assistance in selecting appropriate gloves.


flag image Consult the section entitled Storage Guidelines for hazardous materials storage requirements, recommendations and information on chemical incompatibility.  Additional requirements are provided below.

  • Store flammable and combustible liquids away from ignition sources (heat, sparks, open flames).
  • Segregate flammable and combustible liquids from oxidizing acids and oxidizers.

Flammable Storage Lockers and Refrigerators

  • Store flammable and combustible liquids totaling more than 10 gallons in one room or laboratory in an approved flammable storage cabinet.  Flammable storage cabinets are designed to protect their contents from fires in the work area.  They can be located under fume hoods or exist as stand- alone units.  Approved flammable storage cabinets are constructed of steel and are equipped with self closing doors with a three point latch arrangement.  Flammable storage cabinets installed as part of laboratory construction and renovation projects shall be connected to the building’s supply and exhaust ventilation system.  The top bung is connected to an outside source of supply air and the lower bung is connected to the exhaust system. This controls vapors and odors and prevents corrosion to the interior.  
  • No more than 120 gallons of Class I, Class II, and Class IIIA liquids, combined, may be stored in a flammable storage cabinet.  Of this total, no more than 60 gallons may be Class I and Class II liquids, combined, and not more than three such cabinets may be in a single fire control area. (i.e., an area that is separated from other rooms/areas by fire walls).
  • Do not store Class I liquids in any basement or pit unless it has an approved ventilation system designed to prevent the accumulation of flammable vapors (refer to OSHA 1910.106 (f)(2)(iii)(b)). A basement is a story of a building or structure having one-half or more of its height below ground level.  For questions or further guidance consult the LBNL Fire Marshal .
  • Ordinary domestic refrigerators and freezers contain electrical components (light bulbs, switches, contacts and motors) that are potential ignition sources which may initiate a fire or an explosion if flammable vapors are present.  Therefore, refrigerators and freezers used for storing flammable liquids must be designed, constructed, approved, and labeled for that purpose. NOTE:  This applies to aqueous ethanol solutions greater than or equal to 15%.  Domestic refrigerator and freezers as well as units that have been modified to remove spark sources are not acceptable alternatives.  Contact Procurement and Property Management for guidance on purchasing refrigerators and freezers.  end flag image

Flammable and Combustible Storage Cans and Other Containers

  • Flammable and combustible liquids may be stored in various containers.  The allowed volume depends on the flammable/combustible class and container material - see Table 1. 

Table 1. Containers for Combustible and Flammable Fluids


Flammable Liquid

Combustible Liquid Class

Container Type








1qt a



end flag image1galend flag image

Metal (other than Department of Transportation (DOT) drums)






Approved safety cans b






Metal drums (DOT specifications)






Approved portable tanks






Gravity-Dispensing Flammable Liquids

Class IB liquids (e.g., ethanol) may be transferred from containers or tanks by gravity through piping, hoses and self- or automatic closing valves that have been reviewed and approved by the Laboratory’s Fire Marshal.   Such transfer operations must be done with spill control and secondary containment.  Moreover, the nozzle and containers must be bonded to each other (i.e., electrically interconnected) to prevent static electricity discharge.

Emergency Procedures

  • Consult the “Emergency Procedures and Equipment” section for emergency actions regarding chemical spill and personal exposure to chemicals.
  • In addition to these requirements, the following applies to flammable and combustible liquid spills:
    • Never use combustible or reactive materials (such as paper towels) to clean up or absorb spills of flammable or combustible liquids.  Keep an adequate number of appropriate spill kits to meet anticipated needs. These are commercially available through VWR Scientific.  Typically, products containing diatomaceous earth are used for absorbing organic solvents.
    • An emergency eyewash and safety shower should be located in all areas where flammable or combustible liquids are used. In the event of skin or eye contact, flush the affected area for at least 15 minutes and report to Health Services for evaluation and treatment.


Last updated: 08/31/2010