Reference · Storage compatibility

Chemical storage compatibility by hazard class

Chemicals are grouped into storage classes by their hazards, then segregated so incompatible classes aren't stored together. Pick a class to see what it can and can't be stored with — or check a specific substance in the matrix.

13 hazard classes3,652 substancesGHS · CAMEO · ADRFree · no signup

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01 · How segregation works

Three verdicts, thirteen classes

The 13 classes make 78 unique pairs, and every pair carries one of three verdicts. Below is how those 78 actually resolve in our matrix.

Never store hard stop

Never store together

32 of 78 class pairs · 41%

The classes react with each other directly — fire, a pressure burst, or a toxic gas release. These need a separate cabinet, bund or room; a shared shelf or a common spill tray does not satisfy it.

Most incompatible classesNever-store

Organic peroxides & self-reactives 9 of 12 Oxidizing acids 9 of 12 Oxidizers 8 of 12 Mineral acids 7 of 12 Organic acids 6 of 12

Counted over all 78 class pairs in the matrix.

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Keep separate distance control

Keep separate

41 of 78 class pairs · 53%

No direct reaction between the classes, but a spill or a fire involving one makes the other markedly worse. The control here is distance — another shelf, a bund, a separate tray or catch pan.

Needs most separationKeep-separate

Compressed gases 12 of 12 Acute toxics 11 of 12 Flammable liquids 8 of 12 Flammable solids 8 of 12 Bases 7 of 12

How much distance is set by local regulation — the class pair only tells you separation is required.

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Compatible verify per substance

Generally compatible

5 of 78 class pairs · 6%

Only 5 class pairs carry no class-level restriction — all of them are listed here. The individual substance still governs: read its own SDS sections 7 and 10 before you fix a layout.

Every compatible pair5 of 78

Flammable liquids ↔ Flammable solids Oxidizers ↔ Oxidizing acids Bases ↔ Cyanides & sulfides Water-reactives ↔ Reactive metals Cyanides & sulfides ↔ Acute toxics

Compatible at class level is a starting point, never a substitute for the substance's own SDS.

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02 · Classes

All 13 storage classes

Grouped by hazard family. Each card carries the substances we hold in that class and how its 12 pairings resolve — never store, keep separate, compatible.

13 classes · 5 hazard families

Flammable 262 substances

Oxidizing 83 substances

Corrosive 95 substances

Reactive 218 substances

Toxic 617 substances

Need one specific substance?

Class-level segregation gets you the shape of the store. For a named chemical, the storage compatibility matrix resolves the verdict against 3,600+ substances by CAS number, and the SDS library carries the full reference page.

SDS Manager

Class-level segregation only holds if the sheet behind every drum is the current one — SDS sections 7 and 10 are what a segregation plan is actually built on, and they change when a supplier reissues. For keeping that library current, version-controlled and reachable by QR code on the store-room door, the solution we recommend is SDS Manager. It also offers SDS authoring and a broader EHS suite.

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Reference aid only — storage-class segregation is a starting point, not a substitute for a substance's Safety Data Sheet or professional judgment. Always verify against SDS sections 7 and 10 and local regulations.