Every year hundreds of fires start in cooking appliances such as fryers, griddles and grills. These fires quickly spread to the hoods and grease filters and then to the ductwork. The most resent well known examples occurred at Heathrow Airport and South Mimms Services. There are two readily available solutions:

A restaurant fire suppression system is used to provide fire protection for restaurant cooking appliances, the hood and ductwork. Since naked flames and large quantities of fat are in close proximity, fire is a very real risk.

M. K. Fire is a registered agent for Ansul R-102 kitchen fire suppression systems. MK Fire can offer the design, installation and servicing of R-102 systems. Each system specifically designed for the kitchen into which it is being installed. M. K. Fire provides a free consultancy and quotation service.

You can see R102 in action by downloading this Video.
 

The R-102 system suppresses fires in the plenum, the filters, cooking surfaces, and the extract duct. When the ANSULEX low pH liquid fire suppressant agent is discharged onto a hot greasy surface, it reacts with the grease, forming a layer of soap-like foam. A reaction called soaponification. This extinguishes the fire by preventing air (oxygen) reaching the fuel (grease) and by cooling the surface.

The basic system consists of an ANSUL-AUTOMAN regulated release assembly, which includes a regulated release mechanism and a liquid agent storage tank, housed within a single enclosure. The system would be activated by fusible link detectors mounted in the hood or manual pull stations. Additional equipment includes: remote manual pull station, mechanical and electrical gas valves, pressure switches’ and electrical switches for automatic equipment and gas line shut off.

Accessories can be added, such as alarms, warning lights etc, to installations as required.

Class F - Wet chemical fire extinguisher
Standard size is a 75f rating unit, contains 6 Litres of extinguishant. 75f rating means the Extinguisher has Extinguished a 75 Litre test fire of cooking oils heated to their Auto Ignition Temperature.

How It Works
The chemicals react with the heat and the frying media creating a crust on the surface with a porridge like consistency ( known as the soaponification) , which extinguishes the fire in normally just a few seconds (5-10). The extinguishant also permeates through the frying media and makes any chance of re-ignition impossible.

Advantages
Safety - extinguisher has a diffuser nozzle at the end of a lance reducing the discharge pressure so that a fine mist covers an area approximately 1.5 x 1.5m, which means it can be sprayed directly onto the surface of the fire without any flash back risk to the operator. At this point, the pan/fryer lid can be closed, heat turned off and operation of the business, using the rest of the range, can continue.

Maximum area of class F fire (Cooking Oil) for which Wet Chemical extinguishers are suitable.
For an extinguisher of a rating 75F the maximum area for two extinguishers would be 0.4 square metres. The maximum area for one extinguisher would be 0.11 square metres.

Cleaning
After a cooling period (2 hours recommended) the pan/fryer can be cleaned out and if the fryer has not been damaged by fire, refilled and put straight back to use. The frying media and extinguishant can be disposed of with normal waste.