It is the industry sector producing the waste. When you look these codes up you will see each code is quite broad in what it covers. Note you use 2003 codes for Hazardous and 2007 for non hazardous.

Phil I only know what the Environment Agency Web site has (though I found similar info elsewhere), when looking this info up for the company I now work for (as I found many variants throughout the business). EA Web site states:- government considered that it would be too problematic for businesses to change this requirement at this time. Although if you can, you should continue to use SIC (2003) codes on consignment notes, we have issued a position statement stating that we will not generally pursue breaches of this requirement. And of course you only need consignments notes for Hazardous waste. Hence my original comment. The breach would be against "The Hazardous Waste Regulations (HWR)" which require the 2003 codes to be used. Chris