Hazardous property code
HP 12Produces toxic gases in contact with water, air or acid
Waste that releases toxic gases when in contact with water or acids.
- Code
- HP 12
- DEFRA code
- HP_12
Sourced from DEFRA’s digital waste tracking reference data, last checked 25 July 2026.
EWC codes that commonly carry this hazard property
3 entries from the UK List of Wastes.
These are EWC entries that typically carry this hazard property, not a determination that any particular load does. Under WM3, whether a hazard property applies depends on the substances actually present and their concentrations — the producer is responsible for assessing each consignment.
- 10 03 08salt slags from secondary productionhazardousSalt slags (secondary aluminium) — release acute-toxic gas (ammonia / phosphine) on contact with water; irritant and ecotoxic.
- 10 03 09black drosses from secondary productionhazardousBlack drosses (secondary aluminium) — release acute-toxic gas on contact with water; irritant and ecotoxic.
- 10 08 08salt slag from primary and secondary productionhazardousSalt slag from other non-ferrous primary / secondary production — releases acute-toxic gas on contact with water; irritant and ecotoxic.
Related
Recording HP 12 on real paperwork?
Waste carrying HP 12 is hazardous, so it moves on a Hazardous Waste Consignment Note rather than a standard Waste Transfer Note. Our free generator produces a compliant PDF in under a minute.
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