Every waste stream gets a six-digit code from the List of Waste, and whether that code is starred decides how the waste must be moved, documented and treated. This is how the code is arrived at, and why guessing is expensive in both directions.
Every waste stream in the UK is classified with a six-digit code from the List of Waste. If the code carries an asterisk, the waste is hazardous, and a different and stricter set of rules applies to how it is stored, moved, documented and treated. Getting the code right is the single decision that determines everything downstream.
How the list is structured
The list is arranged by the process or industry that produced the waste, not by what the material looks like. The first two digits are the chapter — for example 13 for oil wastes, 15 for packaging, 20 for municipal wastes. The next two narrow it to a sub-chapter, and the last two identify the entry itself. So the same physical substance can take different codes depending on where it came from, which is why the first question is always about the process rather than the drum.
Absolute and mirror entries
Some entries are absolute: the waste is hazardous, or it is not, and no assessment changes that. Many are mirror entries — a starred code and an unstarred code sitting side by side, covering the same material with and without a dangerous property. A mirror entry is a question, not an answer. You have to establish which side of it your waste falls on by assessing the hazardous properties HP1 to HP15 against the concentrations of the substances actually present.
That assessment is made on evidence: safety data sheets for the products involved, process knowledge, and where those are not enough, laboratory analysis of a representative sample. Judging by eye is not evidence, and residue at the bottom of a vessel is frequently not the same waste as the product the vessel held.
Why guessing costs money in both directions
Under-classification is a breach: hazardous waste moved on a transfer note rather than a consignment note, to a site with no permit for it, is a problem for the producer as well as for everyone who touched it afterwards.
Over-classification is quietly expensive. Treating a whole stream as hazardous because one component might be adds a consignment note, a restricted list of destinations and a substantially higher gate fee to every load, for years, when segregating that component at source would have removed the problem entirely.
A short checklist
- Start from the process that produced the waste, then find the chapter.
- Establish whether the candidate entry is absolute or a mirror.
- For mirror entries, assess HP1 to HP15 using safety data sheets, process knowledge or analysis — and keep that evidence.
- Record the code, the reasoning and the date. A classification is a decision you may be asked to justify later.
- Re-check when the process changes. Codes are attached to processes, and processes drift.