Waste classification toolkit


Even with the best efforts to manage resources efficiently, every business will end up with some unwanted materials which need to be taken off site. It is essential to know whether these fall within the legal definition of “waste” or “hazardous waste”.

Why is it necessary to classify waste?

All waste producers have a legal duty of care and can be prosecuted if the waste is not managed in compliance with all the relevant legislation.

How to go about classifying waste

Waste or not waste?

EU Waste Framework Directive 2008/98/EC defines waste as anything which is, or has to be, discarded by the holder — whether it is recyclable or not.

Hazardous or non-hazardous?

  1. Before embarking on the classification procedure, it is worth noting that the following commonplace waste streams are almost invariably hazardous:

    • anything containing asbestos

    • waste agrochemicals (eg weedkiller)

    • fluorescent light tubes

    • old computer monitors

    • waste engine oils

    • cleaning or DIY products which carry a white warning diamond, even if only a small amount is left in the container

    • infectious clinical waste (but not sanitary products, nappies, etc from healthy people).

  2. Is the waste “absolute hazardous” as defined by Appendix A to WM3 European Waste Catalogue? See Assessment of Hazardous Waste for further explanation of the four types of entry.

    1. Absolute hazardous — coded red (no further classification required: it is definitely hazardous).

    2. Absolute non-hazardous — coded black.

    3. Mirror hazardous — coded blue (may be hazardous).

    4. Mirror non-hazardous — coded green.

  3. What hazardous substance does it contain? If the waste is mirror hazardous, find out if the waste contains any of the hazardous substances listed in EC Regulation 1272/2008 on the Classification, Labelling and Packaging of Substances and Mixtures. (This assessment is normally carried out by a specialist waste contractor or chemist on behalf of the waste producer).

    The easiest way to find out whether a specific chemical is hazardous is to use the ECHA search engine. See also Hazardous Waste Charts where the hazardous constituents, hazardous properties, EWC codes and ADR labelling requirements (road transport) for some hazardous waste objects are given.

  4. What is the concentration of the hazardous substances? Waste is hazardous if it possesses one or more of the 15 Hazardous Properties listed in the directive.










    Specific target organ toxicity (STOT) and aspiration hazard


    Acute toxicity












    Releases toxic gases






    After disposal, produces a hazardous leachate, etc.

    If the concentration of a hazardous substance exceeds the appropriate threshold laid down in WM3, the whole waste stream has an HP. WM3 lists the threshold concentrations for each hazardous property, which are summarised in a table here.


    It is the concentration, not the quantity that matters: very small quantities of hazardous substances still qualify as hazardous waste when discarded.

    For explosive, oxidising and flammable hazards, thresholds are not specified in WM3, so testing is required.

Acceptable in landfill or not?

Is this waste acceptable in landfill, and if so, must it go to a hazardous landfill?

Any waste going to landfill needs to meet the waste acceptance criteria (WAC) established under the EU Landfill Directive. The WAC for hazardous waste landfill are very detailed and substance-specific. Any assessment of these would be done by a specialist analytical laboratory.

In the normal way, inert wastes such as brick, concrete and stone from demolition work do not require testing and can be sent directly to an inert landfill. However, if there is a possibility that the waste might be contaminated with materials such as oils, chemicals, plastic or asbestos, it must be tested and evaluated against the WAC.

Active or inactive?

One further classification system for waste relates solely to the Landfill Tax. Waste destined for landfill must be classified as active or inactive. This distinction is important because inactive waste attracts a much lower rate of Landfill Tax. Active waste is essentially biodegradable waste, whereas inactive waste is basically inert construction and demolition waste — but the criteria used are not the same as those used for WAC.

Last reviewed 2 October 2018