Ductworks Fire Protection
The relative complexity of any ductwork system passing through different fire compartments and the relevance of the system’s function in ambient as well as fire conditions can make the selection of a suitable ductwork system difficult.

Fire performance requirements of ductwork and a wide range of solutions for the protection of steel ductwork and for self-supporting systems using PROMATECT®-H, PROMATECT®-L500 and PROMATECT®-50 are provided in this section.

For particularly onerous conditions where high impact strength  is  required or for use  in aggressive environments,  Promat has developed  a  range  of  systems using PROMATECT®-S high impact board.

General Design Considerations
Factors which should be considered when determining the correct specification to ensure a ductwork system will provide the required fire performance include:

  • Required fire exposure
  • Hanger support
  • Movement joints
  • Ductwork functions
  • Required fire performance
  • Steel ductwork
  • Air flow & leakage
  • Penetration through walls/floors
  • Supporting structure
  • Others such as acoustics performance, thermal insulation, water tolerance, strength, etc.
Coated Steel Ducts
PROMAPAINT® FD Water Based Intumescent Coating for Steel Ducts
- Standard duct span maximum up to 1250mm
- For larger dimensions of duct, please consult Promat.
  • 120 minutes fire resistance FRL 120/120/-


Post Cladding Steel Ducts
PROMATECT®-H Post Cladding Steel Ducts
- Standard duct span maximum up to 1500mm
- Wide duct span between 3000mm to maximum 6000mm
  • 120 minutes fire resistance FRL 120/120/-
  • 120 minutes fire resistance FRL 120/120/30 (for BS 476: Part 24 only)
  • 120 minutes fire resistance FRL 120/120/120 (for BS 476: Part 24 only)
  • 240 minutes fire resistance FRL 240/240/-
  • 240 minutes fire resistance FRL 240/240/120 (for BS 476: Part 24 only)
  • 240 minutes fire resistance FRL 240/240/240 (for BS 476: Part 24 only)

PROMATECT®-L500 Post Cladding Steel Ducts
- Standard duct span maximum up to 1500mm
- Wide duct span between 3000mm to maximum 6000mm
  • 120 minutes fire resistance FRL 120/120/120
  • 120 minutes fire resistance FRL 120/120/120 (for Australia only)
  • 240 minutes fire resistance FRL 240/240/240

PROMATECT®-S Post Cladding Steel Ducts
- Duct span maximum up to 10 metres
  • 120 minutes fire resistance FRL 120/120/30 (for Duct type B only)
  • 120 minutes fire resistance FRL 120/120/120
  • 240 minutes fire resistance FRL 240/240/30
  • 240 minutes fire resistance FRL 240/240/60
  • 240 minutes fire resistance FRL 240/240/240

PROMATECT® 50 Post Cladding Steel Ducts
- Standard duct span maximum up to 1200mm
- Wide duct span maximum up to 3000mm
  • 120 minutes fire resistance FRL -/120/120


Self-Supporting Ducts
PROMATECT®-H Self-Supporting Ducts
- Duct span maximum up to 10 metres
  • 120 minutes fire resistance FRL 120/120/-
  • 120 minutes fire resistance FRL 120/120/120
    (with 1-layer mineral wool clad externally)
  • 180 minutes fire resistance FRL 180/180/90 (for Duct type A only)
  • 240 minutes fire resistance FRL 240/240/30 (for Duct type B only)
  • 240 minutes fire resistance FRL 240/240/30
  • 240 minutes fire resistance FRL 240/240/240
    (with 1-layer mineral wool clad externally)

PROMATECT®-L Self-Supporting Ducts
- Duct span maximum up to 10 metres
  • 120 minutes fire resistance FRL 120/120/-
  • 240 minutes fire resistance FRL 240/240/-

PROMATECT®-L500 Self-Supporting Ducts
- Duct span maximum up to 10 metres
  • 30 minutes fire resistance FRL 30/30/30
  • 60 minutes fire resistance FRL 60/60/60
  • 90 minutes fire resistance FRL 90/90/90
  • 120 minutes fire resistance FRL 120/120/120
  • 240 minutes fire resistance FRL 240/240/30
  • 240 minutes fire resistance FRL 240/240/240 (for Duct type B only)

PROMATECT®-S Self-Supporting Ducts
- Duct span maximum up to 10 metres
  • 120 minutes fire resistance FRL 120/120/-
  • 120 minutes fire resistance FRL 120/120/60
  • 120 minutes fire resistance FRL 120/120/30
  • 180 minutes fire resistance FRL 180/180/180
  • 240 minutes fire resistance FRL 240/240/-
  • 240 minutes fire resistance FRL 240/240/120
  • 240 minutes fire resistance FRL 240/240/180
  • 240 minutes fire resistance FRL 240/240/240

Note: FRL */*/* (Fire Resistance Limit — *Stability / *Integrity / *Insulation)