Explosion Venting/Suppression Q&A
Answered September 15th, 2011 by Expert:
Metal dusts are very tricky when it comes to indoor venting systems such as the REMBE Q-Rohr-3. With your particular application, aluminum, the Kst is low but the immediate temperature increase in the event of an incident needs to be considered before determining that an indoor venting system will be effective for this situation. For this reason, generally, metal dusts are not included in ATEX approvals. You will need to have the dust tested by the manufacturer to verify that an indoor venting system is a viable option.