59.1. Open dust collectors: Every open collector for combustible dust or any other suspended matter presenting a fire or explosion hazard and used in the wood industry may be placed and installed inside a building(1) if it is not connected to a sander or abrasive planer with mechanical feed;
(2) if its capacity does not exceed 2.4 m3 per second;
(3) if the fan motor is designed for Class II or III locations according to the Canadian Electrical Code, First Part, Nineteenth Edition, CSA Standard C22-10-04 with Québec Amendments;
(4) if it is emptied as needed sufficiently often to ensure safety and collecting efficiency;
(5) if installed at least 6 m from a work station, a travelway or an emergency exit, unless a protective blast screen, such as a steel sheet, a fire-resistant synthetic sheet or a gypsum wall, is installed between the station, the travelway or the exit and the open dust collector if it is not possible to comply with that distance; and
(6) where there is more than one open dust collector, if the collectors are at least 6 m apart, unless a protective blast screen, such as a steel sheet, a fire-resistant synthetic sheet or a gypsum wall is installed between the collectors if it is not possible to comply with that distance.
For the purposes of this section, “open dust collector” means equipment for the separation of air from solid particles designed and used to remove dust and having the following features:(1) filtering is done by dust-laden air passing through a filtering element that gathers dust inside the filter and allows clean air to return to the ambient air;
(2) the filtering element is not enclosed or installed in a rigid casing;
(3) the filtering element is not shaken mechanically or by pulsed air jets;
(4) the filtering element is under positive pressure; and
(5) the cleaning of collected dust is neither continuous nor mechanical.