Hazardous Substance Location - clarification please Hi Matt
The trigger quantities and classes are clear enough (well, relatelively). The Class 5 stuff above seems to be more to do with what is in storage (closed containers) vs what is being manufactured or used (potentially open containers). There are some similar provisions for the flammables (e.g. used as fuel) and toxic/ corrosive substances. If you compare the values in the Schedule from r12.2 and r12.8, with the values in r12.17 - they're basically the same except special case for farms, chlorine and permanent gases. Again, there are "special cases" for other classes too.
What isn't clear in the Regs (because they don't have definitions for "Place" or "Location"), is the meaning of the phrase "place within a workplace", where you may need one or more Hazardous Substance Location(s) if you exceed trigger levels. That was the basis of my question.
But again, that WorkSafe guide that Meihana shared does give an interpretation and definition that seems very clearly to me to say that it is about storing substances in a single location - and not the whole site (or workplace. Further - it then specifically says that means you can split quantities below threshold values and not need a Compliance Certificate.
Although the guide seems to be part of a suite of documents for Agrichemicals, it does say that it applies to flammable and oxidising substances as well as toxic and corrosive ones.
So again, for me at least, that WorkSafe Guide does seem to remove the uncertainty about WorkSafe NZ interpretation (whatever the intent was), and so I will be looking for triggers at a single location and then checking separation between them. From a risk perspective I think that also makes sense as it means if there is an incident - which will usually be at a single location not a whole site - the consequence will be limited.