Smoke exhaust ductwork
Wikimedia Commons has media related to Smoke Exhaust Ductwork. |
Smoke exhaust ductwork, in Europe, is typically protected via passive fire protection means, subject to fire testing (typically to ISO6944) 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. In North America, fireproofed ductwork may be used for the purpose of smoke exhaust, but it is more common to use unfireproofed return air ductwork, whereby no fire testing or listings are employed to qualify the ductwork for this use. Evidence of this North American practice can be found in the 2010 National Building Code of Canada, 3.2.8.8. Mechanical Exhaust System.
Means of construction
Similar to pressurisation ductwork, smoke exhaust can be built using:
- ordinary sheet metal with external fireproofing treatment; or
- a proprietary duct that is inherently fire-resistant; or
- suitably stiff fireproofing materials, such as calcium silicate.
The primary difference between pressurisation and smoke exhaust ducting is that one pressurises an area, while the other reduces the pressure through exhausting smoke.
Some smoke exhaust ductwork requires no fireproofing if the smoke is not expected to be at elevated temperature.
Markets
Smoke exhaust ducting systems for land-based use are found in most industrialised nations. In North America, the primary purpose is to comply with building codes. Grease ducting is closely related and highly regulated in North America as well; its main purpose is exhaust of grease-laden vapours from commercial cooking operations, as opposed to smoke exhaust from accidental building fires.
Requirements
Full scale fire testing must include 3-dimensional exposures to ductwork as well as the firestop system. Installations must meet the listing.
Trade jurisdiction
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.
Gallery
Rad- und Schwimmsporthalle Berlin, Smoke Exhaust Ductwork made of calcium silicate and plaster fireproofing boards
See also
- Passive fire protection
- Pressurisation ductwork
- Grease duct
- Calcium Silicate
- Fireproofing
- Firestop
- FM Global
- HVAC
- Listing and approval use and compliance
- Smoke
- Fire
- Emergency evacuation
External links
- ULI list of subject related standards
- Rad- und Schwimmsporthalle Berlin
- ISO6944 - 2008 Fire containment -- Elements of building construction -- Part 1: Ventilation ducts