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20 01 37* Wood containing hazardous substances

EWC / List of Waste code · Last checked 21 October 2026 · Applies across the UK (England, Wales, Scotland and Northern Ireland)

Hazardous Mirror entry (hazardous side)

Official description: “wood containing hazardous substances”

Where it sits: chapter 20 (municipal wastes (household waste and similar commercial, industrial and institutional wastes) including separately collected fractions), section 20 01 (separately collected fractions (except 15 01)).

In plain English

Separately collected wood that contains hazardous substances.

Read our guide: hazardous wood →

What the hazard status means

This is one half of a “mirror” pair. Use this hazardous code if the waste contains hazardous substances above the thresholds, or has hazardous properties. You must assess the waste first, usually by knowing exactly what it is made of or by sampling and testing it.

Its mirror entry

20 01 38 Wood other than that mentioned in 20 01 37 Not hazardous

Using this code

Write the code on the paperwork when waste is passed on: a waste transfer note for non-hazardous waste, or a consignment note for hazardous waste (called special waste in Scotland).
Choose the code from where the waste came from first (the chapter), then what it is. If a load is mixed, you may need more than one code.
The waste must go to a site whose permit allows that code. A registered carrier can tell you which codes they accept: check a waste carrier.
Businesses have a duty of care to describe their waste correctly.

Other codes in section 20 01

20 01 01 Paper and cardboard Not hazardous
20 01 02 Glass Not hazardous
20 01 08 Biodegradable kitchen and canteen waste Not hazardous
20 01 10 Clothes Not hazardous
20 01 11 Textiles Not hazardous
20 01 13* Solvents Hazardous
20 01 14* Acids Hazardous
20 01 15* Alkalines Hazardous
20 01 17* Photochemicals Hazardous
20 01 19* Pesticides Hazardous
20 01 21* Fluorescent tubes and other mercury-containing waste Hazardous
20 01 23* Discarded equipment containing chlorofluorocarbons Hazardous
20 01 25 Edible oil and fat Not hazardous
20 01 26* Oil and fat other than those mentioned in 20 01 25 Hazardous
20 01 27* Paint, inks, adhesives and resins containing hazardous substances Hazardous
20 01 28 Paint, inks, adhesives and resins other than those mentioned in 20 01 27 Not hazardous
20 01 29* Detergents containing hazardous substances Hazardous
20 01 30 Detergents other than those mentioned in 20 01 29 Not hazardous
20 01 31* Cytotoxic and cytostatic medicines Hazardous
20 01 32 Medicines other than those mentioned in 20 01 31 Not hazardous
20 01 33* Batteries and accumulators included in 16 06 01, 16 06 02 or 16 06 03 and unsorted batteries and accumulators containing these batteries Hazardous
20 01 34 Batteries and accumulators other than those mentioned in 20 01 33 Not hazardous
20 01 35* Discarded electrical and electronic equipment other than those mentioned in 20 01 21 and 20 01 23 containing hazardous components Hazardous
20 01 36 Discarded electrical and electronic equipment other than those mentioned in 20 01 21, 20 01 23 and 20 01 35 Not hazardous
20 01 38 Wood other than that mentioned in 20 01 37 Not hazardous
20 01 39 Plastics Not hazardous
20 01 40 Metals Not hazardous
20 01 41 Wastes from chimney sweeping Not hazardous
20 01 99 Other fractions not otherwise specified Not hazardous

This page explains the code in plain English. It is not a classification of your waste. The official List of Waste and the classification guidance decide which code applies, and you are responsible for the code you use.