Powered Air Respirator in use clearing, cutting, mulching

Used the mask for 2:30hrs until it went flat today.  Cut and mulched biddy bush on the property. That brings total battery time to 6 hours on one charge.  There was heaps of dust and very fine almost cotton-like seeds from the biddy bush and cuttings. This airborne dust and particles covered the CleanSpace pre-filter cover.  The same material  eventually clogged my Kubota tractor air filter and radiator.  Personally the CleanSpace mask was great - I was breathing fresh clean air the whole time while all around me it looked like a dust storm!  Llew (Bathurst, NSW)