Kitchen Fire Suppression Solutions
The SafetyChef™- EnviroMist™ System is based on innovative “T” technology of using water mist to extinguish fire. It has been designed to protect professional cooking equipment in restaurants, canteens, on ships, yachts, large catering areas, hospitals, hotels and all other types of industrial kitchens against fire. This low pressure, double media, environmentally safe system uses compressed nitrogen and water to produce very fine particles of water mist (55-75 microns). Thanks to specially designed nozzles and rotors installed inside the cylinders this systems has high capabilities to extinguish burning edible oil fumes utilizing the parallel oil cooling effect. Water mist within these parameters is used to extinguish class F fires.
The system design is specific to each kitchen and is dependent on the dimensions of the cooker hood, the extraction/ventilation ducting, category of protection, cooker hood type and cooking equipment to be protected. All SafetyChef™ – EnviroMist™ Systems are LPCB and SABS approved.
The SafetyChef™-EnviroMist™ System is 100% Eco-Friendly and has absolutely no environmental impact. This also means that the system has little to no clean-up required after discharge and is completely safe for people – no toxicity or thermal breakdown.
Two Categories of Protection System
- Equipment Specific Local Protection – designed to protect fixed pieces of cooking equipment with localised application of specially designed nozzles.
- Complete Coverage or Total Flooding – Designed to protect all elements of cooking equipment, fixed/unfixed, below the cooker hood.
Two Types of Cooker Hoods
- Wall Mounted – Cooker hood fixed to a side wall with one row of cooking equipment.
- Island Type – Larger Cooker Hoods placed within the centre of the kitchen, usually allowing for two rows of cooking equipment.
Various types of supply units can be used for kitchen extinguishing systems. They can differ with number of cylinders, actuation mechanism and type of detection. Cylinders with rotors inside are filled with water up to 72% of cylinder capacity and then pressurized with nitrogen to 15 bar at 20°C. Size and quantity of cylinders depends on the total volume of water required, which in turn results from the number of nozzles used and the discharge time of the system.
Discharge Piping Network
Piping is a set of pipes and different hydraulic elements necessary for connecting supply unit with fire extinguishing nozzles. Piping must consist of 3/8”, ½”, ¾” or 1” diameter, 316 stainless steel pipe and fittings.
The main fire extinguishing line is installed along the front edge of the cooker hood. It consists of CSFH type or type H multi nozzles. The type and number of nozzles used depends on the length of protected area and distance between the cooker hood and worktop.
- All equipment is LPCB and SABS approved
- Safe for people – no toxicity or thermal breakdowm
- 100% Eco-Friendly –no environmental impact.
- Suitable for Class F Fires
- Cooling Effect – reduces temperature rapidly
- Mist Blanket – shielding from radiant heat
- Safe on equipment – no thermal or static shock
- Economic Agent – relatively inexpensive compared to other extinguishing agents
- Readily available – in adequate quantities under most circumstances.
- Easy to refill – only requires de-ionized water and nitrogen
- Zero or little clean-up required
- Automatic and manual actuation
Fire Detection and System Actuation
Detection and actuation unit – the detection system gives a signal to the actuation unit, which automatically activates the fire extinguishing system. The System can also be triggered manually.
Fire detection provides signal actuating extinguishing system. SafetyChef™-Enviromist™ Systems use four types of detection, depending on customer requirements and technical specifications.
- Mechanical detection system with fusible links or heat sensitive glass bulbs – The sensors are placed behind filters in critical locations. Fusible links are selected after measuring operational temperature under the hood in places where detectors will be placed. It is recommended to choose melting temperature of fusible links at least 30⁰C higher than the measured temperature. This detection system can work with fusible links or heat sensitive glass bulbs.
- Pressure fusible plug detection system – This detection system consists of piping under constant pressure, with fusible plugs mounted along its length. Melting of a plug causes pressure drop and actuation of the system. Selection method of the detectors is the same as for fusible links. Detectors are placed behind filters and, in every ventilation duct.
- Pneumatic tube detection system – This system is based on pneumatic tube, which melts at designated temperature causing pressure drop and actuation of the system. Pneumatic tube is placed behind filters.
- Linear heat detection cable (LHDC) or digital detection system – This detection is based on a special sensing cable – local temperature rise causes melting of the insulation and closing of the electric circuit. The resulting signal opens the small solenoid valve which provides pressure to main pneumatic valve for actuation.
The task of actuation units is to automatically (after receiving signal from detection) open the main valve. The system can be equipped with an actuation sensor, which can give signal to outside mechanisms, such as alarm, gas cut-off valve etc. There’s always a manual actuation button as well. Depending on the chosen detection system you may use different actuation units.
- Mechanical actuation unit with gas cartridge – The mechanical actuation unit which is used with fusible link detection system. Signal from detection is changed to pneumatic signal (from the gas cartridge), which then opens the supply unit’s main valve.
- Pneumatic actuation unit – The Pneumatic actuation unit with pilot cylinder is used for pressure detection – fusible plug or pneumatic tube detections. Pressure drop in the system will open the main valve.
- Pneumatic Differential Valve – The Pneumatic differential valve is used for pressure detection, fusible plug or pneumatic tube detections. Pressure drop in the system opens the valve.
- Electric actuation unit – While using linear heat detection system, electric signal from detection cable opens auxiliary solenoid valve, which causes pressure from manifold to open main pneumatic ball valve. It is highly recommended to use a conventional control panel to operate the LHDC detection system.
Brigit™ Systems strongly suggests that all commercial kitchens be equipped with at least 1 GreenMist™ handheld fire extinguisher, as an added safety precaution.