5 Common Misconceptions About California §5164: Storage of Hazardous Substances

California's Title 8, Section 5164 sets strict rules for storing hazardous substances like flammables, corrosives, and oxidizers in industrial settings. Yet, even seasoned EHS pros trip over its nuances. I've audited dozens of facilities where these myths led to citations—and near-misses.

Misconception 1: Small Quantities Mean No Rules Apply

Teams often think "if it's just a few gallons, §5164 doesn't touch it." Wrong. The regulation applies to any storage of hazardous substances, regardless of amount, with quantity limits kicking in for specific classes—like no more than 60 gallons of Class I liquids outside cabinets.

In one Bay Area warehouse I consulted for, a "small" drum of solvent sat unprotected, sparking a Cal/OSHA inspection flag. Exemption? None. Always check Table 5164(a) for thresholds and segregate from ignition sources from the start.

Misconception 2: Fire Cabinets Are Optional for Everything

Not every hazardous substance needs a cabinet, but flammables and combustibles do—up to 60 gallons per cabinet indoors. People mix this up with §5165 (spray finishing), assuming cabinets cover all bases.

• Flammables: Mandatory cabinets for excess quantities.
• Corrosives: Spill containment trays suffice, but cabinets help if flammable too.

We once retrofitted a client's lab after they stored acids in open shelves. Result? Compliant, spill-free ops. Reference NFPA 30 for cabinet specs to align with §5164.

Misconception 3: Segregation Only Matters for Flammables

§5164(d) demands separating incompatibles—flammables from oxidizers, acids from bases—yet sites store corrosives next to flammables without a second thought. This ignores reaction risks like spontaneous combustion or toxic gas release.

Picture this: a SoCal fab shop where bleach and ammonia shared space. One spill away from disaster. Use distance, barriers, or dedicated areas per the reg. Pro tip: Map your storage with a compatibility chart from OSHA 1910.106 as a cross-check.

Misconception 4: Secondary Containment Is Always Required

Common error—assuming every drum needs a berm. §5164 focuses on approved containers and spill control measures, but secondary containment is explicit only for certain corrosives and when quantities exceed limits.

I've seen overbuilt setups wasting space and underbuilt ones failing audits. Balance it: use diking for liquids over 55 gallons outdoors, per §5164(e). EPA's SPCC rules complement this for larger ops, but Cal/OSHA leads here.

Misconception 5: Ventilation Fixes All Storage Issues

Good airflow helps, but §5164(g) requires it only for enclosed spaces with vapors exceeding 25% LEL. Don't rely on fans to bypass segregation or cabinet rules.

During a Central Valley plant walkthrough, exhaust fans masked poor storage—until a vapor buildup test failed. Install per ACGIH guidelines, monitor with detectors, and train staff on limits.

Bottom line: Master §5164 by auditing annually against its tables. Pair with GHS labeling under §5194 for full compliance. Your facility—and Cal/OSHA—will thank you. Dive into the full text at dir.ca.gov for the latest amendments.