Fire Dampers are not acceptable in Kitchen Extract systems as they can become unserviceable with exposure to grease and become impossible to clean. Excessive heat in Kitchen Extract duct can activate the fusible links in fire dampers. (BS 9999:2008 Clause 188.8.131.52 and 184.108.40.206). Commercial kitchens must have separate and independent extract systems (BS 9999:2008 Clause 33.4.7).
Commercial kitchen extract ductwork should be tested for Type A (fire outside) and Type B (fire inside.) Both tests are required to prevent flammable grease from either catching fire when it passes through an adjacent compartment or, if the grease itself is already alight maintaining the fire within the duct, or causing a fire to start within the adjacent compartment by radiant heat. Under DW 172 (Specification for Kitchen Ventilation Systems) and TR 19 (B&ESA publication, guide to Good Practice- Internal Cleanliness of Ducts). It is recommended that Fire Rated Access Doors should be installed at three metre intervals or a change in aspect or direction where possible for future cleaning and inspection. Internal surfaces must be smooth to enable easy cleaning. Square Bends with turning vanes should be avoided.
Fully welded Mild Steel and Stainless Steel “Grease Tight” ductwork and fittings are also available.
|System Description||Material||Stability & Integrity||Insulation|
|Kitchen Extract||Galvanised Or Stainless||Up to 4 Hours||Up to 60 mins*|
*Insulation values are obtained through the application of specific insulation
All systems are manufactured and installed to satisfy the requirements of recognised ductwork specifications including DW 144 and DW 172
Fire Rated access doors (uninsulated and insulated) are available in the following sizes:
- 200 x 125 Clear Opening
- 300 x 150 Clear Opening
- 450 x 250 Clear Opening
- 525 x 350 Clear Opening
- 625 x 450 Clear Opening
Note! Insulated Access Doors are made to order depending on the required rating of the system.
Trusted by the trade
Our professional approach and continual investment in the training of our staff, technology and manufacturing methods ensure you receive the very best product and service. We are ISO 9001 and Investors in People accredited and manufacture to a high DW144 standard by our own skilled and experienced sheet metal fabricators.
Non Coated galvanized ductwork has significant commercial and environmental savings on systems using intumescent or flame retardant coatings that require energy and chemicals to degrease, etch, prime , paint and dry but also alleviates the inherent problems of damaging these coatings during assembly and installation and compromising the fire resistance of a coated system.
Fire Rated Ductwork:
- 2 hour ductwork
- 4 hour ductwork
- Kitchen Extract Duct
- Smoke Extract Duct
- Fume Extract Duct
All fire rated ducting is manufactured to the Caswell Firesafe specification. See our About Caswell Firesafe page for further information.
Email us now to obtain a quote for your requirements.