one extra row of in-rack sprinklers in the longitudinal
flue space at the 3 foot (0.914 m) level. The first level
of storage shall not be below the one foot (0.305 m) level
to facilitate easier cleanup of spills.
220.127.116.11 Aqueous Film Forming Foam (AFFF). AFFF sprinkler systems are an
appropriate means of protecting flammable and combustible liquids. AFFF
systems may be used where permitted by NFPA 30.
Hazardous Materials Storage Areas. Provide a minimum of 2-hour fire
rated construction between hazardous materials storage areas and those used
for storage of flammable and combustible liquids. These areas shall be
labeled as "Hazardous Materials Only," and shall also be labeled as to the
type of sprinkler protection present in each room. Provide automatic
sprinklers at the ceiling level as well as one mandatory level of in-rack
sprinklers (i.e., in the flue space between the rack and the wall) located at
or slightly above the midpoint with respect to overall storage height. Design
ceiling level sprinkler densities based on the storage of Class IV commodities
in NFPA 231C. In water reactive areas, provide automatic sprinklers with an
OS&Y valve to be locked in the closed position. Provide a metal sign
indicating the OS&Y valve is to remain locked in the closed position unless a
fire is detected in the storage area. The sign can be attached to a chain and
connected to the OS&Y valve or fastened permanently to the wall provided it
does not interfere with the operation of the valve. Locate the OS&Y valve
outside the water reactive storage area.
Hazardous Waste Storage Facilities. For hazardous waste storage
facility requirements, refer to the following:
NFPA 43C, Storage of Gaseous Oxidizing Materials
NFPA 43D, Storage of Pesticides in Portable Containers
NFPA 49, Hazardous Chemicals Data
NFPA 490, Storage of Ammonium Nitrate
18.104.22.168 Fire Protection for Hazardous Waste Storage Facilities.
following minimum criteria shall be provided:
Exterior Fire Walls
(1) Exterior walls shall have a 4-hour fire rating when the
facility is attached to a structure or it is located within 10 feet (3 m) of
another building or property line.
Exterior walls shall have a 2-hour fire rating when the