pswallace":1a3w83q4 said:
Hi, can anyone advise on what kind of respirator I should be looking for ? . . mainly for mdf and general saw dust. I cant really afford the high-end equipment but iv,e looked at some half mask types around £20-30.
Point 1: IMO, if you can't afford a decent face-mask you're better off not cutting MDF or other materials with 'dangerous' dust. (In fact, you're probably better off not using any machinery which produces fine dust, either.) Your lungs would cost far more than the cost of a good respirator to replace, and as an asthmatic I can assure you that not being able to breathe properly is no fun at all - I'd gladly pay a couple of hundred quid for my existing respiratory condition to go away, I'd certainly advise people against getting a new one!
Point 2: It's not the mask that's the really important part, it's the filters. The mask just needs to provide a tight seal to your face; I'm fine with one of the nose-and-mouth rubber-seal ones myself (with a so-called '
Van Dyke' beard - albeit the kind that gets called a goatee rather than the cool Musketeer kind) but some people with full beards have seal problems and are probably better off with full-face masks. That said, if you're content with a half-face mask there are certainly some decent-enough ones around within your budget.
However, even a full-face mask is next to useless with the wrong filters. The off-the-shelf ones the mask comes with are probably specced to just keep house dust out or something equally useless, if you're working with fine dust (MDF dust seems particularly bad, apparently it's glued together with something nasty) you really need P2-rated filters at the very least, preferably P3 if you can find them. Make sure that the filters will fit on the mask you buy, as you'll almost certainly have to buy them separately unless you mail-order.
(As it goes, "P" means "particulate", and they're rated from 1-3, with 1 being "better than nothing", 2 being "OK" and 3 being "fairly good" or something. I think there's percentage-particles-filtered meanings, but I'm not sure how accurate they are anyway. If you're going to use the same mask for spraying, you need an A-rated filter, which will filter out organic compounds. If you need to do both, you can certainly get filters which are both A- and P-rated.)
Also check the use-by date on the filters before you buy them, if you can - they do degrade, and I've certainly seen some lying around on the shelves of Wickes that were already two years past their use-by date before they were sold!
As a general rule, if you can smell whatever it is you're worried about, your filters aren't good enough.