Oddly enough I was reading the same document this week.
In my non-expert view you may wish to seek other forms of guidance on this subject rather than relying on the HSE alone. The HSE guide is written specifically for vacuum cleaners for use where there is a potentially explosive dust atmosphere. Very unhelpfully it then advises that with a torn bag or filter then virtually any vacuum cleaner used in a business or domestic environment could also explode. Since a filter tear or bag failure is entirely likely over the life of the vacuum, then by following the HSE guidance note you don't have much option but to use a very expensive machine specifically manufactured for such areas.
The reality is that in the history of vacuum cleaners, and millions of machines, there has never been a case where an explosion has happened (based on my web searches but if anyone knows of any I would be very interested).
Absence of an explosion is obviously not an absence of risk, but would indicate a flaw in the HSE guidance.

Thanks, I appreciate the comments but I am not convinced there is any requirement for ATEX equipment. The guidance is quite clear in that if the area has a hazardous classification then ATEX equipment is required - Our area is not classified as such.

We've more experience with flammable vapours than explosible dusts but using that logic I'd expect an ATEX vacuum to have additional protection of the windings and electrical system etc on the same lines as other intrinsically safe equipment and the risk is from what in the air -not what is drawn up. The dust burden would have to be greater than our present circumstances by several orders of magnitude for this to be a factor (if not the type of vacuum would be the least of our worries!).

Looking at the risk, there's a lot about potential or possible but little or nothing saying where's its actually occurred, as pointed out there's tens, hundreds of thousands of them out there, if we follow the guidance the risk is low and it becomes hard to justify as RP.

I hope I am not horribly wrong but I thought the advice was fairly straightforward and logical, we don't need ATEX vacuum but there are some sensible considerations to make when making the selection. It really does boil down to the issue of airflow over the motor.

I'll ask the major manufacturers but would must have got to consider their advice to be slightly biased - sorry for being cynical - as they have vested interest in pushing the ATEX requirement (though I might be pleasantly surprised).

Thanks for the input

Have a look at this

Motorhead - thanks for the link, some useful, entertaining and downright daft links from that. Some of the OSHA stuff was particularly informative, even if well beyond the scale of our operations.

Jim - I know where your coming from, we have previously looked at flour dust and I thought it would be rated higher than low combustibility, but its the HSE guidance that defines it as low combustibility, if we can't trust this as an information source then what can we trust?

I'd like to stress that the guidance http://www.hse.gov.uk/food/dustexplosionapp1.htm is meant for non-hazardous environments (i.e. No zone 20,21,22) under DSEAR, not the opposite indicated in earlier posts. As I see things, its perfectly acceptable to use a standard (commercial / industrial) vacuum so long as the construction is such that ignition risk are minimised. It just getting the specification right and finding a supplier that's seems difficult and I suspect the major players will not fill the gap when they can sell you an ATEX rated vacuum at 5 x the cost.

Jon