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  • EHS specialist looking into a flammable safe cabinet

    Introduction

    Understanding and complying with OSHA and Cal/OSHA regulations for flammable liquids helps organizations protect their employees, avoid legal issues, and contribute to a safer and more efficient workplace. Benefits include:

    • Safety: The primary hazards associated with flammable liquids are explosion and fire. OSHA regulations help mitigate these risks by providing guidelines on proper storage, handling, and usage. This reduces the likelihood of accidents that could cause serious injuries or fatalities.
    • Legal Compliance: Adhering to OSHA standards is a legal requirement for businesses. Non-compliance can result in significant fines and legal consequences. Ensuring compliance helps businesses avoid these penalties and maintain a good standing with regulatory bodies.
    • Workplace Efficiency: Proper management of flammable liquids can enhance overall workplace efficiency. By following OSHA requirements, businesses can create a safer and more organized work environment, which can lead to increased productivity and reduced downtime due to accidents.
    • Environmental Protection: OSHA laws also help prevent environmental contamination. Proper storage and handling of flammable liquids reduce the risk of spills and leaks, which can have severe environmental impacts.
    • Employee Well-being: Ensuring a safe workplace is essential for employee morale and well-being. When employees feel safe, they are more likely to be productive and engaged in their work.

    Scope

    This document is confined to communicating the occupational safety requirements around the limits for flammable liquid use and storage.
    Outside of flammable liquid rooms or warehouses, the OSHA storage limits depend on the following issues:

    • The presence of a Fire Area (segregated by 1 hr. fire resistant construction)
    • Flammable liquid classification (1, 2, 3, or 4)
    • The type of container in which the liquid is stored
    • Location in Office, Educational, and Institutional Occupancies
    • Size and number of flammable storage cabinets in a Fire Area (Cal/OSHA)
    • Location (inside/outside) flammable liquid storage cabinet or room, or warehouse
    • Additional operations and requirements

    Cal/OSHA Comparison to OSHA (Federal)

    The California Department of Industrial Relations is responsible for enforcement of occupational safety and health standards under the federal Occupational Safety and Health Act of 1970.i 

    •  California Code of Regulations, Title 8, Chapter 4, Subchapter 7. Group 20 Flammable Liquids, Gases and Vaporsii
    • US Code of Federal Regulations, Part 1910, Subpart H, 191.106 Flammable Liquidsiii

    As an agreement state, California has adopted OSHA’s standards with some additional state-specific provisions under the California Code of Regulations (CCR), Title 8. The relevant section for flammable liquids is 8 CCR § 5533, which generally aligns with OSHA’s standards but contains some specific nuances.

    1. Fire Area Summary

    An area of a building separated from the remainder of the building by construction having a fire resistance of at least one hour and having all communicating openings properly protected by an assembly having a fire resistance rating of at least one hour.
    Unlike the Fire Code, neither OSHA nor Cal/OSHA regulations limit the number of fire areas in a building nor is there variation by floor, unless it is a flammable liquid warehouse.

    2. Definitions & Classifications

    For both sets of regulations, the Globally Harmonized Standard (GHS) definitions and categories of flammable liquids are followed. The most flammable is Category 1, with the least flammable, Category 4.

    OSHA Liquid, Flammable, FP ≤ 93 C  

    Table 1. Flash Points, Boling Points, Categories and GHS Hazard Codes & Statements
    CategoryFlash PointBoiling Point Hazard CodeHazard Statement
    1< 23 C≤ 35 CH224Extremely flammable liquid and vapor
    2< 23 C> 35 CH225Highly Flammable liquid and vapor
    3FP ≥ 23 C & ≤ 60 C         H226Flammable liquid and vapor    
    4FP > 60 C & ≤ 93 C H227Combustible liquid

     

    Table 2. Classification Exemplar
    CategoryExamples
    1diethyl ether, isopropylamine, furan, propylene oxide, trifluoroacetone, 1-pentene
    2gasoline, ethanol, (tert-butyldimethylsilyl)acetylene, (trifluoromethoxy)benzene
    3kerosene, (bromomethyl)cyclopropane, (diethylamino)acetone, 2-butanol   
    4diesel, (+)-menthone, (+)-terpinen-4-ol, styrene oxide, 1,2-butanediol

    3. Location in Office, Educational and Institutional Occupancies


    Storage shall be limited to that required for operation of office equipment, maintenance, demonstration, treatment, and laboratory work. All liquids in laboratories and at other points of use shall meet the following storage provisions:

    Container and Storage Requirements

    • A container is any vessel of 60 U.S. gallons or less capacity used for transporting or storing flammable or combustible liquids.
    • A safety can is a listed container of not more than five gallons capacity, having a spring-closing lid, spout cover and a flame arrester and so designed that it will safely relieve internal pressure when subjected to fire exposure.
    • A closed container is sealed by means of a lid or other device that neither liquid nor vapor will escape from it at ordinary temperatures.

     

    Table 3. Maximum Allowable Size of Containers and Portable Tanksiv 
    Container TypesCat. 1*Cat. 2*Cat. 3Cat. 4 
    Glass or Approved Plastic1 pt1 qt1 gal1 gal
    Metal (excluding DOT)1 gal5 gal5 gal5 gal
    Safety Cans2 gal5 gal5 gal5 gal
    Metal Drums (DOT)60 gal60 gal60 gal60 gal
    Approved Portable tanks    660 gal660 gal660 gal660 gal

    *Up to 1 gal maximum – reference for conditions
    1 pt (1/8 gal, 473 mL), 1 qt (1/4 gal, 946 mL), 1 gal (3.785 L), 5 gal (18.92 L), 60 gal (227 L), 660 gal (2,498 L)

    OSHA Fire Area Quantity Limits

    • No container for Category 1, 2, or 3 flammable liquids shall exceed a capacity of one gallon except that safety cans can be of two gallons capacity.
    • Not more than 10 gallons of Category 1, 2, or 3 flammable liquids combined shall be stored outside of a storage cabinet or storage room, except in safety cans.
    • Not more than 25 gallons of Category 1, 2, or 3 flammable liquids combined shall be stored in safety cans outside of a storage room or storage cabinet.
    • Not more than 60 gallons of combustible liquids shall be stored outside of a storage room or storage cabinet.

    Quantities of flammable and combustible liquids in excess of those set forth in this section shall be stored in an inside storage room or storage cabinet. There are different requirements for dorms and industrial plants.

    4. Size and Number of Flammable Storage Cabinets in a Fire Area (Cal/OSHA)

    Fire Marshal approved flammable storage cabinets qualify for OSHA requirements. In California, others can also apply based on the details in section 5533 (b) (https://www.dir.ca.gov/title8/5533.html)
    Not more than 120 gallons of Category 1, 2, 3, and 4 flammable liquids may be stored in a storage cabinet. Of this total, not more than 60 gallons may be of Category 1, 2, and 3 flammable liquid. Not more than three such cabinets may be in a single fire area. There are specific design and test requirements for flammable liquid cabinets.

    5. Location in or out of a Flammable Liquid Storage Cabinet or Room, or Warehouse

    Inside Storage Rooms for flammable liquids have specific requirements such as being liquid-tight where the walls join the floor or an open-grated trench inside of the room which drains to a safe location. Also, electrical appliances must be approved for Class I, Division 2 Hazardous Locations, and there must be mechanical ventilation with specific flows. There are requirements for aisles and stacking. 
     

    Table 4. Inside Storage Rooms Limits
    Automatic Fire Protection Provided   Fire Resistance    Maximum Floor Area    Total Allowable Quantities Gals/sq ft/floor area
    yes2-hour500 sq. ft.10
    no2-hour500 sq. ft.4
    yes1-hour150 sq. ft.5
    no1-hour 150 sq. ft.2

    The code allows for Flammable and Combustible Liquid Warehouses and Storage Buildings.v 

    Table 5. Flammable and Combustible Liquid Warehouses and Storage Building Limits
    Liquid Category    Storage Level    Protected Storage* Maximum Per Pile, Gals
    (# of 55 gallon drums)
    Unprotected Storage Maximum Per Pile, Gals 
    (# of 55 gallon drums)
    1Ground & Upper Floors2,750, (50)660, (12)
    BasementNot permittedNot permitted
    2Ground & Upper Floors5,500, (100)1,375, (25)
    Basement    Not Permitted    Not Permitted
    3 FP<100FGround & Upper Floors    16,500, (300)    4,125, (75)
        
    Basement    Not permitted    Not permitted
    3 FP > 100F    Ground & Upper Floors    16,500, (300)    4,125, (75)
        
    Basement    5,500, (100)    Not permitted
    4 and FP>199.4F    Ground & Upper Floors    55,000, (1,000)    13,750, (250)
        
    Basement    8,250, (450)    Not permitted

    * A sprinkler or equivalent fire protection system installed in an approved manner. (Numbers in parentheses indicate corresponding number of 55-gallon drums.)

    There are specific requirements for the use of ‘indoor portable tanks’ in Flammable and Combustible Liquid Warehouses and Storage Buildings in the same section.

    California OSHA has specific requirements and limits the amount of flammable liquid storage outside buildings in 8CCR5542 (https://www.dir.ca.gov/title8/5542.html). This applies to containers and portable tanks.

    In all areas where flammable and combustible liquids are stored, fire control devices, such as sprinkler systems, hoses, or portable fire extinguishers are required. Additionally, open flames, smoking, and water reactives are not allowed in the same room as flammable and combustible liquids.

    In California article 146 (8CCR5606 through 5612) there are specific requirements for valves and piping of flammable or combustible liquids. The materials must be compatible with the fluids and when softened by exposure to fire they meet the requirement of ANSI B31. The pipes and vales also must be protected against corrosion.

    6. Additional Operations and Requirements

    Other requirements apply to Dip Tanks, Spray Coating operations, Bulk hydrogen, Bulk oxygen, Electrical equipment, Industrial Plants, Processing Plants, Service Stations, Tank Storage, Bulk Plants, Refineries, Chemical Plants, Wineries and Distilleries, Logging, and Sawmills.

     

    https://www.osha.gov/laws-regs/oshact/section_18  
    ii  https://www.dir.ca.gov/Title8/sb7g20.html  
    iii https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.106   
    iv EXCEPTIONS:
    (1) Medicines, beverages, foodstuffs, cosmetics, and other common consumer items, when packaged according to commonly accepted practices, shall be exempt from the requirements of 5532(a).
    (2) Glass or approved plastic containers of no more than 1-gallon capacity may be used for a Category 1 or 2 flammable liquid if:
    (A) Such liquid either would be rendered unfit for its intended use by contact with metal or would excessively corrode a metal container so as to create a leakage hazard; and
    (B) The user's process either would require more than 1 pint of a Category 1 flammable liquid or more than 1 quart of a Category 2 flammable liquid of a single assay lot to be used at one time, or would require the maintenance of an analytical standard liquid of a quality which is not met by the specified standards of liquids available, and the quantity of the analytical standard liquid required to be used in any one control process exceeds one-sixteenth the capacity of the container allowed under Table FL-2 for the category of liquid; or
    (3) The containers are intended for direct export outside the United States.

    v In California, in these cases, the limits are in 8CCR5541 (https://www.dir.ca.gov/title8/5541.html).

     

    Russ Vernon, Ph.D.
    Russ Vernon, Ph.D.
    EH&S Business Development Manager
    Risk and Safety Solutions