VANCOUVER - British Columbia's approximately 300 saw mills have been told they have until May 9th to take care of any sawdust problems they may have.

The order from WorkSafe BC follows two sawmill explosions that have left four dead, many injured, and whole communities wounded economically by the loss of major employers.

Investigators are looking at whether sawdust was a factor in Monday's fiery blast at a mill in Prince George and the explosion in January that killed two people in Burns Lake.

WorkSafe has told BC's mills that have to conduct thorough inspections and eliminate any combustible dust problems.

Some sawmill workers say sawdust problems have grown with the harvesting of tinder dry trees killed by pine beetles.