Airmaster Fire Rated Ductwork
Air Master was established in the year 1987 in the United Arab Emirates. Since then it has been known to be the pioneers in the field of manufacturing of air-distribution and air-control products like HVAC Air ducts, Splitter damper, Grilles, Diffusers, Louvers and Dampers. Having a successful startup of “Sheet Metal Ducting” in 2017, Air Master has now come up with a new product in line with the existing fire safety products – Fire Rated Ductwork.
“AIR MASTER” fire rated ductwork (AMFRD) is a non-coated type galvanized steel sheet met-al ductwork, tested in accordance with BS 476 part 24 and International standards in inter-nationally accredited laboratories. It is manufactured by specialized technical team using computerized state-of-the-art sheet metal duct manufacturing machines.
Air Master Fire Rated Ductwork is designed in a such a way that it is easy to install, light in weight and cost effective for the contractors, fulfilling stringent criteria of international codes of fire safety in buildings.
Fundamental Characteristics of Fire Rated Ductwork
The methods followed for the fire resistance of walls and floors penetrated by ventilation ducts in building regulatory requirements and under the guidance of BS 9999:
Protection using Fire Resisting Enclosures
Protection using Fire Resisting Ductwork
It is most important to choose the most suitable fire resisting ductwork system for its intended application area to ensure that the ductwork fire performance meets the requirements of the relevant application.
Airmaster Fire Test at APPLUS Lab , Spain
Features of Fire Rated Ductwork
Successful testing and assessments are done for the duct size range up to 6000 millimeters in compliance with BS 476 part 24 and ISO 6944-1985 at internationally accredited Applus+ Laboratories at Barcelona, Spain.
Tested in horizontal as well as vertical orientation separately under cellulosic (standard time Vs. temperature curve) fire conditions and successfully achieved over 120 minutes of fire resistance for integrity and stability of
- Duct A (Fire Outside the ductwork)
- Duct B (Fire Inside the ductwork).
A global product assessment and certification of the fire resistance performance for ventilation and smoke extraction ducts is being done by Applus+ Laboratories
- ISO 6944-1985
- BS 999
- Mechanical Ventilation System
- Car Park Smoke Extraction System
- Dual Ventilation / Smoke Extraction System
- Stairwell Pressurization System
- Kitchen Extraction System
- AMFRD-01A (without insulation)
- AMFRD-01B (without insulation)
- AMFRD-02A (with insulation)
- AMFRD-02B (with insulation)
FIRE RATED DUCTWORK TYPES:
Fire Ducts for Ventilation
Air Master Fire Rated Ductwork helps maintain pressurization systems and ensures compartmentation. The integrity of the duct and its ability to function must be maintained in the event of a fire. The Ductwork is a non-coated system, suitable for installation in multi-compartment, single compartment, stud wall, solid wall, and aerated concrete floors. A comprehensive set of support systems is provided. Penetration seals guidance is provided with detailed drawings.
Smoke Extract Duct
Smoke is recognized as the major killer during fire outbreaks. It can spread quickly to nearby buildings that are quite remote from the original flash, threatening life and damaging property. Stairwells and elevator shafts frequently become smoke logged, blocking evacuation routes and preventing firefighters and other rescue teams from doing their critical jobs. Air Master Smoke Extract ductwork is a key element of a fire strategy, by safely channeling smoke out of the building.
Frequently Asked Questions about Fire Rated Ducts
Duct used for the extraction of smoke in case of fire and designed to provide a degree of fire resistance
- Normal Ducts:
No protection against fire and doesn’t prevent fire spread.
Lighter construction, not fit for fire resistant application.
Tested for air leakage only (if deemed necessary)
- Fire Rated Ducts :
Restricts fire spread from Outside and Inside duct up to certain time.
Stronger and more rigid than normal ductwork.
Tested for different international standards for fire resistance (BS, EN, ASTM, UL etc)
- Stability: Ducts and supports are intact
- Integrity: Ducts are free of cracks and holes
- Insulation: Limit temperature on Insulation surface
- Kitchen Extraction: Limit the fire inside the duct
- Smoke Extract: Limit the reduction in cross section
- BS 476-24
- EN 1366-1,-8,-9
- EN 13501-4
- ISO 6944
- ASTM E2816-12
Standard fire tests to which specimens of constructions are subject to, are based on the Cellulosic time/temperature curve, as defined in various national standards, e.g. ISO 834, BS 476: part 20, DIN 4102, AS 1530, etc.
This curve is based on the burning rate of the materials found in general building materials and contents.
1049 º C
Type A: Fire Outside (generally for applies ventilation ducts)
Type B: Fire Inside (extraction ducts)
In any building/premises both these conditions are possible in the event of fire
Sometimes contractors wrap normal ventilation ducts with Rockwool or non-combustible insulation of any thickness/density. This is absolutely wrong and is considered detrimental to building safety. If the ductwork loses stability / integrity, Insulation will fail as it will move with the collapse of ducts.
It is very important to understand that ‘We can have an Integrity-Stability rating without Insulation rating, but NOT an Insulation rating without Integrity-Stability’.
Insulation is totally dependent upon the ductwork maintaining its integrity and stability.
Overall, it’s the system (DUCT + INSUALTION) that works. It delivers the highest possible protection against fire. Therefore, it is important for an Insulated Fire rated duct to be tested and certified as a single system.
Coated Ducts :
- Special paint/coating applied on to the steel ducts
- Lighter in construction
- Limited temperature exposure 400oC Max (for Insulated)
- For Stability & Integrity full std. TT curve exposure
Non-coated Ducts :
- Bare steel ducts with relatively heavier construction (GI/MS/SS finish)
- Exposed to full Standard time-temperature curve (for both Insulated and Uninsulated)
Ducts coated with Fire Resistant paint may not completely qualify as Fire Rated Duct.
Coated ducts can qualify for Stability & Integrity criteria when exposed to full time-temperature curve however it does not qualify for insulation criteria.
Insulation criteria for coated ducts is limited to maximum 400º C temperature only.
It has to be as tested and certified as a single system. Insulation and installation method will be recommended by certified manufacturers based on the assessment approvals from testing and certification body.
Ducts have to be supported strictly as per manufacturers specifications and installation guidelines. Support system assessment must be based on test performance.
Wall penetration design is exactly as per test conditions. Manufacturers’ will provide necessary training and guidelines to install it.
The primary function of smoke duct is to carry hot gases from the place of fire out in to the atmosphere. A fire damper will close and prevent smoke extraction functions.
Kitchen extract ductwork poses a specific risk due to the presence of combustible grease lining (cooking oil fumes become grease) inside the ductwork. When ductwork passes through multiple compartments, there is a risk from a fire in a compartment outside the kitchen. This can cause the grease inside the duct to ignite and spread fire inside the ducts throughout the building.
Insulation on the ducts in the kitchen provide no protection. A fire in a commercial kitchen will be subject to the kitchen suppression systems and compartmentation structure.
Fire dampers are used to maintain compartmentation in the event of fire, to restrict spread of fire from one location to another to prevent migration of fire through the building.
Due to the presence of grease inside the ducts, fire dampers become inoperable. Hence, they offer no protection against fire and damage.