NC STATE Home Page NC STATE UNIVERSITY - Environmental Health and Safety 2620 Wolf Village Way Cmpus Box 8007, Raleigh NC 27695  Phone 919.515.7915 FAX 919.515.6307 NC STATE Home Page

FLAMMABLE AND COMBUSTIBLE LIQUIDS

Purpose

A flammable material is any liquid, solid or gas that will ignite easily and burn rapidly. Materials that are flammable are of concern due to their ability to render damage to property and more importantly, to injure or cause death of workers.

Objective

The storage, issue, use and disposal of flammable and combustible liquids falls under the rules and regulations promulgated under OSHA, the National Fire Protection Association and the University policy.

Responsibility

All users of flammable and combustible material must follow this section

Classification of Flammable and Combustible Liquids

"Flammable liquid" refers to any liquid having a flash point below 100 F. Such flammables are Class I liquids. These liquids are subdivided into three classes. The following is an illustrative list of common flammable liquids:

Class IA Flash point below 73 F, boiling point below 100 F

acetaldehyde ethyl chloride petroleum ether
collodion methyl ethyl ether propylene oxide
ethyl ether pentane


Class IB Flash point below 73 F, boiling point at or above 100 F

acetone ethyl acetate methyl alcohol
benzene ethyl alcohol methylcyclohexane
butyl alcohol gasoline toluene


Class IC Flash point at or above 73 F and below 100 F

amyl acetate isopropanol turpentine
amyl alcohol methyl alcohol xylene
dibutyl ether styrene


"Combustible liquid" refers to any liquid having a flash point at or above 100 F. Combustible liquids are subdivided as follows:

Class II Flash point at or above 100 F and below 140 F

acetic acid fuel oil no. 44 mineral spirits
camphor oil methyl lactate varsol
cyclohexane hydrazine kerosene


Class III Flash point at or above 140 F and below 200 F

aniline furfuryl alcohol phenol
carbolic acid naphthalenes pine oil


Containers for flammable and combustible liquids shall not exceed the maximum capacities listed in the OSHA standards shown below. Follow the size limitations for containers to prevent ignition of flammable liquids by sparks from static discharge during pouring operations.


Maximum Capacity of Containers for Flammable and Combustible Liquids

Container Liquids Type Flammable Liquids Combustible
Container Type Class 1A Class 1B Class 1C Class II Class III
Glass or approved plastic* 1 pt 1 qt 1.1 gal 1.1 gal 5 gal
Metal 1.1 gal 5 gal 5 gal 5 gal 5 gal
Safety Cans 2.6 gal 5 gal 5 gal 5 gal 5 gal
*Approved means approved or listed by either Underwriter's Laboratories or Factory Mutual Engineering Corporation.

Exception No. 1: Glass containers as large as 1.1 gal shall be permitted to be used if needed and if the required purity would be adversely affected by storage in a metal or an approved plastic container, or if the liquid would cause excessive corrosion or degradation of a metal or an approved plastic container.

 


Maximum Quantities of Flammable and Combustible Liquids Permitted Outside of Storage Cabinets As Indicated By Type of Space

Maximum Total Quantities
Types of Space and Containers Class I and II Liquids Combined Class III Liquid
Laboratory (instructional or research)
(Liquids in containers per Table 1)
Glass, approved plastic, or metal safety can
5 gal
10 gal
10 gal
20 gal
Printing Operations (Dept and similar size activities)
(Liquids in containers per Table 1)
Glass, approved plastic, or metal safety can
3 gal
5 gal
5 gal
10 gal
Shop (Departmental, instructional and similar size)
(Liquids in containers per Table 1)
Glass, approved plastic, or metal safety can
5 gal
10 gal
10 gal
20 gal

If quantities of flammable or combustible liquids are required in excess of the quantities shown in Table 2, then storage cabinets must accommodate these excess quantities.

Storage Outside Building

Storage of flammables and combustible liquids outside of buildings shall be only in accord with the detailed and specific requirements of OSHA and State Fire Code, as to capacity, location, construction, spill containment, security and fire control.

Pouring and Transfer of Liquids

To avoid sparks from the discharge of static electricity during pouring operations of Class I and Class II liquids, the storage containers and the container being filled must be bonded and grounded. Bonding is the provision of an electrical path between the storage container and the container being filled. Grounding is provided by an electrical path from the storage container to an earth ground.

Construction and Capacity of Storage Cabinet

Storage cabinets for flammable and combustible liquids shall be either metal or wood construction. Their design and construction are to limit the internal temperature to not more than 325 when subjected to a 10 minute fire test using the standard time/temperature curve as set in the Standard Methods of Fire Tests of Building Construction and Materials: NFPA 251-1969. All joints and seams shall remain tight and the door shall remain securely closed during the fire test. Construction shall be in accordance with detailed OSHA requirements (1910.106(d)(3)).

The following is the maximum size capacity for storage cabinets of flammable and combustible liquids:

 

Maximum Capacities of Storage Cabinets in various Locations

 

Laboratories 45 gals
Printing Operations 30 gals
Shops 45 gals

The total quantity of flammable and combustible liquids in a laboratory, cabinets. There shall be no more than one 45 gallon capacity storage cabinet or two 30 gallon capacity storage cabinets in any one room. Label storage cabinets with conspicuous lettering "Flammable-Keep Fire Away." Post "No Smoking" signs in the room and on the entrance doors.