How the EPA’s SPCC rule sizes containment for drums and IBCs, how it differs from the RCRA and fire code figures, and the calculator set up for each.
Under the EPA’s SPCC rule, secondary containment must hold the entire capacity of the largest single container, plus enough freeboard for rain. It applies at facilities storing more than 1,320 US gallons of oil above ground, counting only containers of 55 gallons or more. Four 55-gallon drums on one pallet need 55 gallons plus freeboard, not 110 per cent of the total.
Open the calculator for the US Hazardous waste Flammable liquids
Oil under SPCC, and hazardous waste under RCRA, for 55-gallon drums and 275- and 330-gallon IBCs. Outdoors, add freeboard for rain to the SPCC figure.
| Store | Stored | SPCC, oil | RCRA, hazardous waste | Calculator |
|---|---|---|---|---|
| One 55-gallon drum | 55 gal | 55 gal (208 L) + rain | 55 gal | Open |
| Four 55-gallon drums | 220 gal | 55 gal (208 L) + rain | 55 gal | Open |
| One 275-gallon IBC | 275 gal | 275 gal (1,041 L) + rain | 275 gal | Open |
| Two 275-gallon IBCs | 550 gal | 275 gal (1,041 L) + rain | 275 gal | Open |
| One 330-gallon IBC | 330 gal | 330 gal (1,249 L) + rain | 330 gal | Open |
| Four drums and one 330-gallon IBC | 550 gal | 330 gal (1,249 L) + rain | 330 gal | – |
US gallons. 55 gallons is 208 litres. The calculator works in litres and converts.
SPCC (40 CFR 112) sizes on the largest container plus freeboard, for oil. RCRA sizes permitted hazardous waste storage on 10 per cent of the total or the largest container, whichever is greater. The International Fire Code, which states and cities adopt, asks for containment above set quantities of flammable and hazardous liquids and adds 20 minutes of sprinkler water indoors, or the 24-hour rainfall from a 25-year storm outdoors. Outdoors, it accepts an approved containment pallet with a sump of at least 66 gallons, kept out of the rain.
The calculator applies all three: pick the United States, then the liquid.
Take the capacity of the largest single container in the containment area and add enough freeboard to hold rain. Four 55-gallon drums on one pallet need 55 gallons plus freeboard. The rule sets no freeboard figure; EPA guidance points to the rainfall from a 25-year, 24-hour storm for outdoor containment.
No. The rule asks for the entire capacity of the largest container plus sufficient freeboard for precipitation. 110 per cent is a common rule of thumb for that freeboard, and some state rules and permits write it in, but the federal rule does not.
It applies where a facility stores more than 1,320 US gallons of oil above ground and could reasonably be expected to discharge oil to navigable waters or shorelines. Only containers of 55 gallons or more count towards the 1,320.
Permitted hazardous waste storage under RCRA needs containment of 10 per cent of the total or 100 per cent of the largest container, whichever is greater. A generator storing under 40 CFR 262.17 has no federal capacity figure, so check your state.
The standards and regulations this page relies on, at their issuing body. Where a market rule is named here, check the current revision before you specify against it.
Figures worked out by our spill pallet calculator, applying each rule as read from the official text on 3 October 2026.
Tell us the drums and IBCs, the liquid and the state. We come back with the containment that passes, its load rating and a quotation.