This Instruction STD from MI-OSHA is too good not to share with those who deal with 1910.106(e) and their flammable liquids safety efforts. It does a nice job comparing the 1910.106 (which is based on the 1968 edition of NFPA 30) with the current NFPA 30 standard.
Inside storage rooms (Liquid Storage Rooms) are normally used:
- when the containers are opened for mixing, pouring, dispensing, or transfer of flammable liquids;
- if the quantity is too large to fit into an approved cabinet;
- if the quantity is excessive for any one fire area; and/or
- if the opened containers cannot be separated from potential sources of ignition.
As defined by NFPA 30 paragraph 3.3.34, Liquid Storage Room is a room used for the storage of liquids in containers, portable tanks, or intermediate bulk containers, has a floor area that does not exceed 500 square feet and may be completely inside of the building; or inside with one common wall; or outside with one common wall of the building.
- the storage is considered to be warehousing ONLY or
- it is “Incidental storage and use of flammable liquids” per paragraph 1910.106(e)(2)
CONSTRUCTION AND VENTILATION OF INSIDE FLAMMABLE LIQUID STORAGE ROOMS
29 CFR 1910.106(d)(4) identifies the requirements for the design and construction of inside storage rooms, including the ventilation requirements in subparagraph (iv). NFPA 30-2015, paragraph 18.6, addresses the same subject with additional and differing requirements.
The portions of 29 CFR 1910.106(d)(4)(iv) apply when a mechanical ventilation system equipped with a control switch located outside of the door, which operates the lights and ventilation system, and requires a pilot light adjacent to the switch if Category 1 liquids with a flash point below 100° are dispensed, will not be enforced if continuous mechanical ventilation is provided.
The following provisions of NFPA 30-2015, paragraph 18.6 will be enforced using General Duty Clause for mechanical ventilation systems provided the system was installed after 1977 in rooms where flammable materials with a flash point below 100ºF are dispensed. (recommended for older systems):
a. A continuous mechanical system shall be used if Category 1 liquids with a flash point,100ºF are dispensed in the room (Para. 18.6).
b. Exhaust air shall be taken from one side of the room, near a wall, within 12″ (300 mm) of the floor (Para18.6.1).
c. Make up air inlet(s) shall be on the opposite side of the room from the exhaust outlet, within 12″ (300 mm) of the floor (Para. 18.6.1).
d. Placement of air inlet(s) and outlet(s) shall enable the system to cause air movement across all portions of the floor (Para. 18.6.2).
e. Exhaust shall be directed to the outside of the building without recirculation. (Exception: A fail-safe, continuous monitoring system with an alarm and capability to stop recirculation and provide full exhaust to the outside in the event that vapor-air mixtures in concentration over ¼ the lower flammable limit are detected, may be used to monitor recirculated air) (Para. 18.6.3).
f. All ducts used for ventilation shall not be used for any other purposes (Para. 6-18.6.4).
g. All ducts used shall comply with NFPA 91, 2015 (Para. 18.64).
h. Inlet(s) located on a wall within the building shall be equipped with a fire door or damper with a fusible link or other approved thermal unit as required in NFPA 91, 2015. Installation shall be as required in NFPA 91, 2015 (Para. 18.6.4.1).
i. Mechanical systems shall provide a minimum of one cubic foot of exhaust air per minute per square foot (0.3 cubic meters / minute per square meter) of floor area, but not less than 150 CFM (4 cubic meters / minute) (Para. 18.6.5).
j. Mechanical ventilation systems for dispensing areas shall be equipped with an air flow switch or other device, inter-locked to sound an audible alarm upon failure of the system (Para. 18.6.5.1).
4. Processing areas where flammable liquids are used should be ventilated to follow NFPA 30 -2015 paragraph 17.11 which says; “enclosed processing areas handling or using class I liquids or class II or II liquids heated to temperatures at or above their flash points where the room temperature is heated to a temperature higher than the flash point shall be ventilated at a rate sufficient to maintain the concentration of vapors within the area at or below 25 percent of the LFL.”
INCIDENTAL STORAGE OF FLAMMABLE LIQUIDS OUTSIDE OF A FLAMMABLE LIQUID STORAGE ROOM
1. When the only operation involved is the storage of flammables in containers or tanks that are closed and remain closed throughout their storage, the storage area shall be considered and referred to as a warehouse as described in paragraph 1910.106(d)(5)(v). In this instance, Tables H-14 and H-15 shall be used.
2. When procedures involve mixing, transferring, or other exposure of the liquid to vaporization through operational procedures in which the containers do not remain closed in the storage area, 1910.106(e)(2)(ii)(a) shall be considered to refer to a storage area and determine the permissible quantities as described in paragraphs (d)(3) or (4). In this instance, Table H-13 shall be used to determine permissible quantities.
3. 1910.106(e)(2)(ii)(b) refers to the amount of flammable liquids that may be stored in any one fire area outside of an approved storage room or cabinet in approved containers. Reference to the SDS with regards to the flashpoints and boiling points are important as it determines the Category.
Category 1 has a flashpoint below 73.4 Degrees F and a Boiling point at or below 95 degrees F.
Category 2 liquids have a flashpoint below 73.4 degrees F and a boiling point above 95 degrees F.
Category 3 includes liquids at or above 73.4 degrees F and below 140 degrees F.
4. 1910.106(e)(2)(iv)(d) is the section which shall be used to cite for failing to use a safety can or closed piping system for transferring flammable liquids at the point of final use. 1910.106(e)(2)(iv)(d) also allows transfer by means of a device drawing through the top, from a container or portable tanks by gravity through an approved self-closing valve, or through a closed piping. NOTE: 1910.106(d)(2)(i) refers to the size of containers (reference Table H-12) and containers meeting D.O.T. requirements
in storage. It does not necessarily require a “safety” can.
Source: https://dli.mn.gov/sites/default/files/pdf/STD_1-5.7_flammable_liquids.pdf