Smoke exhaust ductwork

File:Mississippi mills nrc irc national fire laboratory smoke exhaust duct.jpg

Enormous smoke exhaust duct used to extract smoke generated during fire testing at National Research Council (Canada)'s National Fire Laboratory in Mississippi Mills, Ontario.

Smoke exhaust ductwork, in Europe, is typically protected via passive fire protection means, subject to fire testing (typically to NBN EN 1366-8) 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, as well as Sections 909.16.2 and 910 of the 2015 International Building Code.

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.

Gallery

• Smoke exhaust duct1.jpg
• Smoke exhaust duct2.jpg
• Smoke exhaust duct3.jpg
• Smoke exhaust duct4.jpg
• Smoke exhaust duct5.jpg
• Smoke exhaust duct6.jpg
• Smoke exhaust duct7.jpg
• GEOFLAM 1.jpg
• GEOFLAM 2.jpg
• GEOFLAM4.jpg
• GEOFLAM5.JPG

Rad- und Schwimmsporthalle Berlin, Smoke Exhaust Ductwork made of calcium silicate and plaster fireproofing boards

See also

• Passive fire protection
• Pressurisation ductwork
• Heat and smoke vent
• Grease duct
• Calcium Silicate
• Fireproofing
• Firestop
• FM Global
• HVAC
• Listing and approval use and compliance
• Smoke
• Fire
• Emergency evacuation

External links

• Smoke Extraction in Buildings Slide Show by Vysakh Manohar
• Approval Standard for Fume Exhaust Ducts or Fume and Smoke Exhaust Ducts
• ULI list of subject related standards
• Rad- und Schwimmsporthalle Berlin
• NBN EN 1366-8 Fire resistance tests for service installations - Part 8: Smoke extraction ducts
• ISO6944 - 2008 Fire containment -- Elements of building construction -- Part 1: Ventilation ducts
• YouTube Return Air Ductwork Video - Return air can be co-opted for cold smoke exhaust in North America
• "Ask the builder" page on return air ductwork. Return air ductwork can be co-opted for cold smoke exhaust in North America
• "Wisegeek" page on return air ductwork. Return air ductwork can be co-opted for cold smoke exhaust in North America