Ontario Ministry of Labour:
Please take note of important information with respect to Dust Collection and the section of the legislation that stipulates location of
dust collector units . A link is included below to: Occupational Health and Safety ActR.R.O. 1990, REGULATION 851INDUSTRIAL ESTABLISHMENTS
Once you click on this link look for Material Handling (45-71), and scroll down for section 65. Note for reference purposes, 0.47 cubic meters per second capacity is equal to 1000cfm. An abbreviated text is below – this is NOT the full act, please click the link above for full information.
Please also note that in section 65, the first criteria for placement of dust collection units is how “ignitable” the material is. If the material is considered ignitable, the dust collection unit must be placed outside, or
(b) in a room used solely for the housing of dust-collecting equipment which is,
(i) separated from the rest of the building by a dust-tight partition having a minimum fire-resistance rating of one hour, and
(ii) constructed to provide explosion venting to the outdoors.
Note that the section above does not apply if:
is used for a wood-working operation other than wood flour manufacturing and having less than 0.47 (1000cfm) cubic metres per second capacity.
You may also find this link helpful as it pertains to Fire/Explosion Hazards in Handling of Combustible Wood Dust