Auto Repair Garage Storage, Dispensing and Hot Work
A 5,000-square-foot auto repair garage stores 90 gallons of Class I flammable liquid in two listed 45-gallon storage cabinets, 60 gallons of Class II combustible liquid in 55-gallon drums outside any cabinet, and 20 gallons of Level 2 aerosol products on open shelving. Technicians dispense Class I liquid from a 55-gallon drum using a hand pump into open pans, and perform hot work with a portable torch within 10 feet of a parts washer. The garage has a vehicle paint booth that is not separately ventilated. The owner wants to add a second 55-gallon drum of Class I liquid and increase aerosol storage to 40 gallons. The building is protected by a sprinkler system and has a fire alarm. The fire code official must evaluate the storage, dispensing, hot work, and paint booth, and decide what permits and controls are required.
1. Assess the flammable and combustible liquid storage arrangement, including the cabinets, drums, and open pans. What corrections are needed?
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The cabinet storage is only part of the problem. The two 45-gallon cabinets may be within their listing limits for Class I, but the 60 gallons of Class II in 55-gallon drums outside a cabinet or approved room is not acceptable storage. The aggregate quantity in the fire area must be compared with the permit thresholds, and the drums need secondary containment and approved ventilation. Dispensing Class I liquid from a 55-gallon drum with a hand pump into open pans is a spill and ignition hazard; dispensing should be through an approved pump or safety cans, with bonding and grounding, spill control, and no open containers. The aerosol products on open shelving need their level and quantity checked against aerosol storage limits. I would require a hazardous-materials inventory and cabinet/room layout before approving any increase.
2. Evaluate the hot work and paint booth conditions. What controls are required before work continues?
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The hot work is the most immediate hazard. A portable torch within 10 feet of a parts washer, with solvent vapors present, requires a hot-work permit, a 35-foot clearance or approved shielding, a fire watch, and extinguishing equipment. The paint booth is also a concern: an unventilated booth can accumulate flammable vapors, and spray operations require approved ventilation, separation, electrical classification and sprinkler protection. Hot work should be prohibited while spraying or until the booth is purged and tested. I would stop the hot work until a permit and checklist are in place, and require the booth to be evaluated as a spray area before continued use.
3. Should the owner’s requested increase-another 55 gallons of Class I liquid and 40 gallons of aerosols-be approved? What is the approval path?
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The requested increase-another 55 gallons of Class I and 40 gallons of aerosols-should not be approved on the current layout. The owner must first bring existing storage into compliance: remove the drums from open storage or place them in an approved cabinet/room, provide dispensing and spill control, and correct the hot-work and booth conditions. Then a new hazardous-materials permit application can be reviewed with quantities, cabinet listings, ventilation, separation and fire protection. I would allow the increase only if the aggregate quantities remain within the code limits and the fire area arrangement is approved. If the quantities exceed those limits, a dedicated hazardous-materials room or a reduction is required.