Smoke Exhaust Ductwork is typically protected via passive fire protection means, subject to fire testing and listing and approval use and compliance. It is used to remove smoke from buildings, ships or offshore structures to enable emergency evacuation as well as improved firefighting.
Similar to pressurisation ductwork, smoke exhaust can be made of
- 1. ordinary sheet metal and then receive external fireproofing treatment, or
- 2. a proprietary duct that is inherently fire-resistant, or
- 3. one may make the duct out of suitably stiff fireproofing materials, such as calcium silicate
Smoke exhaust ducting systems are in land-based use in most industrialised nations of the world. In North America, the primary use is used to comply with building codes. Grease ducting is closely related and highly regulated in North America as well, except that the purpose is different, being the exhaust of grease laden vapours from commercial cooking operations, as opposed to smoke exhaust from accidental building fires.
Full scale fire testing must include 3-dimensional exposures to ductwork as well as the firestop system. Installations must meet the listing.
In the case of exterior treatments on top of ordinary ductwork, as well as ducting made of fireproofing boards, the most suitable and most often used trade is the insulation trade. In the case of proprietary systems with inherent ratings, the sheet metal trade is responsible for the work. Most often the work is tendered and executed by contractors with significant passive fire protection experience.
