Enter your largest single container and total stored volume to get the secondary-containment sump size the common SPCC rule of thumb expects (the larger of 100% of the biggest container or 10% of total stored volume), plus the spill kit class and sorbent chemistry that match your liquids.
How the sizing logic works
Containment: the widely used SPCC-derived rule sizes secondary containment to the larger of the single biggest container or 10% of total stored volume — a 55-gal drum among four drums (220 gal total) needs at least 55 gallons of sump. Our 1-drum (15-gal sump) and 2-drum (30-gal sump) platforms cover point-of-use and paired-drum storage; note a single full drum failure exceeds either sump, which is why platforms pair with response kits rather than replace them.
Kits: match absorbency class to the largest credible release — bucket kits for machine areas, 20-gal drum kits for drum zones, 30-gal overpack kits at bulk storage (the overpack container itself can swallow a failed drum). The full decision logic is in our best spill kits guide and the spill control collection.
Chemistry: universal absorbs everything including rainwater (its outdoor weakness); oil-only repels water and floats; acid work needs neutralizing media plus chemical-resistant gloves and splash goggles. Facility-scale orders route via bulk & business orders.
This calculator provides general guidance using common SPCC sizing conventions — not legal, engineering, or compliance advice. WC Safety participates in the Amazon Associates Program; product links may earn us a commission.