DD 8458-1:2010
Fixed fire protection systems. Residential and domestic watermist systems. Code of practice for design and installation
This Draft for Development (DD) gives recommendations for the design, installation, water supplies, commissioning, maintenance and testing of watermist systems with automatic nozzles installed in residential occupancies not exceeding 20m in height and domestic occupancies.
It primarily covers watermist systems used for life safety, but might also provide property protection.
Watermist fire suppression system maintenance is not complex but is essential. It is important that owners and occupiers pay particular attention to precautions issued by the watermist system supplier, such as the avoidance of obstructions to the watermist nozzle, or the painting of the watermist nozzle or its mounting.
Watermist fire suppression systems have demonstrated their value in assisting the protection of life and property in industrial and commercial applications for many years. The advent of watermist nozzles that operate at an earlier stage in the development of a fire, together with the recognition that the largest numbers of deaths from fire occur in the home, have led to the introduction of watermist fire suppression systems specifically designed for residential and domestic occupancies.
A correctly designed, installed and properly maintained watermist fire suppression system can detect, suppress and control a fire at an early stage of development, and activate an alarm. Operation of the system will rapidly reduce the rate of production of heat and smoke, allowing more time for the occupants to escape to safety or be rescued.
Residential and domestic watermist fire suppression systems consist of a water supply, filter, check valve, stop valve, priority demand valve (where required), automatic alarm system (both internal and external) and pipework to automatic watermist nozzles. Automatic watermist nozzles operate at a pre-determined temperature to discharge water over a known area below. The flow of water thus initiated causes the sounding of an alarm. Only those watermist nozzles operate which are individually heated above their operating temperature by the heat from the fire.
This publication is not to be regarded as a British Standard.
Contents of DD 8458-1:
- Foreword
- Introduction
- 1 Scope
- 2 Normative references
- 3 Terms and definitions
- 4 General recommendations
- 5 System actuation
- 6 Design and installation
- 7 Installation, commissioning and documentation
- 8 Maintenance
- Annexes
- Annex A (normative) Room fire test for watermist systems with automatic nozzles
- Bibliography
- List of figures
- Figure 1 – Cylinder-based system
- Figure 2 – Fire pump and town mains system
- Figure 3 – Fire pump and tank system
- Figure A.1 – Room corner layout (showing a two-nozzle arrangement)
- Figure A.2 – Between two nozzles room layout (showing a two-nozzle arrangement)
- Figure A.3 – Beneath a nozzle room layout (showing a two-nozzle arrangement)
- Figure A.4 – Corner fire test ignition and fuel package
- Figure A.5 – Beneath a nozzle and between two nozzles fire test ignition and fuel package
- Figure A.6 – Ventilation test layout (showing a two-nozzle arrangement) for door location A
- Figure A.7 – Ventilation test layout (showing a two-nozzle arrangement) for door location B
- List of tables
- Table A.1 – Fire test maximum temperatures
