Intermediate bulk containers
The intermediate bulk container (IBC) is quickly emerging as the container of choice for companies transporting or storing bulk liquids or dry goods. These containers can potentially hold flammable or combustible liquid and may be exposed to fire. UL addresses IBCs based on the scale of the fire.
Reduced scale fire performance
The reduced-scale fire tests are conducted in an enclosed room with a 30 ft. high ceiling and fitted with four open sprinklers. Two IBCs are filled to their rated capacity with water and one gallon of heptane and stacked on a square steel test tray. Contained flowing heptane is ignited for a period of 20 minutes with sprinklers discharged at 0.60gpm/ft2 after one minute.
The Fire Protection Research Foundation developed testing for IBCs. After extensive testing, it was determined that different IBC construction features affect performance when exposed to fire.
Large-scale fire performance
The large-scale tests are conducted in an enclosed room with a 30 ft. high ceiling and fitted with 36 automatic sprinklers arranged to flow at 0.60gpm/ft2 upon activation. Eight IBCs are filled to their rated capacity with water and one gallon of heptane and arranged in a 2x2x2 storage array. Uncontained flowing heptane fire is delivered over a 30 minute period.
IBCs can be suitable for storing combustible and flammable liquids. However, a certification process is needed to identify units that are capable of complying with established fire test criteria.
The latest edition of NFPA 30 allows the use of IBCs for the storage of level II and level III combustible liquids provided that the storage vessels are subjected to standardized fire tests as described in UL 2368, the Standard for Safety of Fire Exposure Testing of Intermediate Bulk Containers for Flammable and Combustible Liquids.
