Post by Steven on Apr 11, 2011 16:10:46 GMT -5
Part. 3 of the Ontario Building Code will redirects the Fixed Extinguishment system to the Ontario Building Code Part. 6 which redirects it to the NFPA 96 standards. The NFPA 96 standard will also then refer to NFPA 12 (CO2 systems), NFPA 13(Sprinklers), NFPA 16(Deluge Foam-Water), NFPA 17(Dry Chemical), NFPA 17A (Wet Chemical).
Fixed extinguishing systems are becoming more in demand because insurance companies are now insisting on it and the Ontario Fire Code requires it. There are two types of systems made; Local Application and Total Flooding systems.
Local application - Designed to deploy extinguishant directly onto the fire such as a head that discharges directly onto a deep fryer.
Total Flooding - Designed to deploy extinguishant into a confined area.
There are two ways each system can be made. These are engineered(unique), and pre-enginered(prepackaged).
Engineered - Calculations and measurements are made uniquely for the equipment. It is designed for the specific equipment its covering. All CO2 systems are engineered!
Pre-engineered - Pre-designed and is sold and installed as a package. It will have predetermined flow rates, pipe sizes, nozzle pressures and extinguishing capabilities.
There are some common terminology in which you need to know;
Abort Control - a control to stop the system from discharging in the event of a false alarm.
Hood - Vapour removal assembly before the filters.
Pleunum - Vapour removal assembly after the filters but before the grease duct.
SYSTEM COMPONENTS
i. Storage Cylinder and Valve -
The cylinder will contain the extinguishant. CO2 cylinders will be much heavier then the dry chemical containers and will not have a gauge to indicate content pressure.
ii. Control Head -
Allows the extinguishant to be discharged from the cylinder, and will sometimes automatically shut down the fuel supply or activate the fire alarm.
iii. Piping system -
The piping in which the extinguishant travels from the cylinder to the discharge heads.
iv. Discharge heads -
Each type will have its own type of head. ie. Duct and pleunum discharge heads will discharge the extinguishant in a fog pattern, while the discharge head over cooking equipment will be in a swirling cloud pattern.
v. Detection Device -
Detect or sense the fire either electronically or mechanically (ie. fusible link). Dry chemical would most likely have a fusible link or a quartzoid bulb. Others may use devices such as smoke detectors or alarms.
vi. Manual Operating Device -
A way of tripping the system manually if in a case where the person notices the fire before the detection device, or to be used in the event of a failure of the detection device.
vii. Automatic Fuel Shut-off -
Automatically shuts off the fuel supply once the system trips. This may also be equipped with a manual reset button.
TYPES OF SYSTEMS:
i. Dry Chemical -
*Dry chemical systems are no longer available.* This system is a combination of both local application and total flooding system. The extinguishant is directed onto the fire and also into the pleunums and ducts. There is two important things that must happen upon actuation:
1) Fuel shut-off device trips
2) Exhaust fans continue to operate (so that the extinguishant gets pulled into the pleunum and duct).
Most of these dry chemical systems are pre-packaged systems. The detection device will be mechanical or electrical; and must be located either above each appliance or above each group of appliances. Dry chemical systems must have class BC extinguishers nearby. The dry chemical systems will remove the o2 and break the chain reaction of the fire.
Pros:
-Costs less
Cons:
-Lengthy shut-down time for clean-up, food contamination and loss.
ii. Carbon Dioxide Systems -
The CO2 system is very similar to the Dry Chemical system except that the CO2 system has a damper in the duct designed to contain the gas, and the fan will be wired to shut down automatically upon actuation of the system. This system is a engineered total flooding system. CO2 systems must have class BC extinguishers nearby. The systems disperses the oxygen in the room, removing the fires energy.
*These are found in special application areas such as computer rooms that contain important documentation, museums, etc.
Pros:
-no clean-up problems, doesn't contaminate food, dissipates rapidly, and if there is a secondary supply of extinguishant the business can resume immediately after the problem has been corrected.
Cons:
-Being an engineered system it is expensive to install, and more expensive to recharge. There is IDLH problems that can occur if it trips in a confined space due to the depletion of oxygen.
iii. Wet Chemical System -
This system uses a liquid chemical called aqueous potassium carbonate; in which forms a soapy foam over the fire. The bubbles in the foam produce carbon dioxide which inerts the surrounding atmosphere. These systems must be hydrostatically tested every 12 years. Wet chemical systems must have class K extinguishers nearby. The wet chemical system cools the fire and removes the o2.
Pros:
-Pre-engineered which costs less.
Cons:
-Some Shut-down time, contamination of food, clean-up to be done.
Sprinklers:
Some buildings might extend their existing sprinkler system into an area of their cooking equipment as long as it meets both requirements of NFPA 13(sprinklers) and NFPA 96(fixed extinguishers). The heads will be SSP with approved special spray nozzles in which can discharge at intermediate, high, or extra high temperature rating. These heads must be replaced annually.
Checks/Tests/Inspections on the systems:
Storage Cylinder - Check the tag to see when it was last serviced (exception of CO2), and that the cylinder is as near as possible to the heads.
Control head - In operating condition, cable leading to the fuel shut-off.
Piping - Clear and free of grease build up
Detection - Free of grease buildup and links replaced annually
Heads - All required appliances protected, heads aiming in correct position, clean and free of grease build up.
Manual Pull Station - Located by means of egress, instructions on how to use posted, question employees to see if they know how to operate it, not obstructed
Hood - free of grease buildup
Filters - Listed type only, cleaned regularly, free of grease, in place
Cooking equipment - Proper clearances from fryer to open flame, minimum splash over to equipment or floors, and protected by a nozzle
Fuel shut off - In place? Is is approved? (i.e. manual reset)
Fixed extinguishing systems are becoming more in demand because insurance companies are now insisting on it and the Ontario Fire Code requires it. There are two types of systems made; Local Application and Total Flooding systems.
Local application - Designed to deploy extinguishant directly onto the fire such as a head that discharges directly onto a deep fryer.
Total Flooding - Designed to deploy extinguishant into a confined area.
There are two ways each system can be made. These are engineered(unique), and pre-enginered(prepackaged).
Engineered - Calculations and measurements are made uniquely for the equipment. It is designed for the specific equipment its covering. All CO2 systems are engineered!
Pre-engineered - Pre-designed and is sold and installed as a package. It will have predetermined flow rates, pipe sizes, nozzle pressures and extinguishing capabilities.
There are some common terminology in which you need to know;
Abort Control - a control to stop the system from discharging in the event of a false alarm.
Hood - Vapour removal assembly before the filters.
Pleunum - Vapour removal assembly after the filters but before the grease duct.
SYSTEM COMPONENTS
i. Storage Cylinder and Valve -
The cylinder will contain the extinguishant. CO2 cylinders will be much heavier then the dry chemical containers and will not have a gauge to indicate content pressure.
ii. Control Head -
Allows the extinguishant to be discharged from the cylinder, and will sometimes automatically shut down the fuel supply or activate the fire alarm.
iii. Piping system -
The piping in which the extinguishant travels from the cylinder to the discharge heads.
iv. Discharge heads -
Each type will have its own type of head. ie. Duct and pleunum discharge heads will discharge the extinguishant in a fog pattern, while the discharge head over cooking equipment will be in a swirling cloud pattern.
v. Detection Device -
Detect or sense the fire either electronically or mechanically (ie. fusible link). Dry chemical would most likely have a fusible link or a quartzoid bulb. Others may use devices such as smoke detectors or alarms.
vi. Manual Operating Device -
A way of tripping the system manually if in a case where the person notices the fire before the detection device, or to be used in the event of a failure of the detection device.
vii. Automatic Fuel Shut-off -
Automatically shuts off the fuel supply once the system trips. This may also be equipped with a manual reset button.
TYPES OF SYSTEMS:
i. Dry Chemical -
*Dry chemical systems are no longer available.* This system is a combination of both local application and total flooding system. The extinguishant is directed onto the fire and also into the pleunums and ducts. There is two important things that must happen upon actuation:
1) Fuel shut-off device trips
2) Exhaust fans continue to operate (so that the extinguishant gets pulled into the pleunum and duct).
Most of these dry chemical systems are pre-packaged systems. The detection device will be mechanical or electrical; and must be located either above each appliance or above each group of appliances. Dry chemical systems must have class BC extinguishers nearby. The dry chemical systems will remove the o2 and break the chain reaction of the fire.
Pros:
-Costs less
Cons:
-Lengthy shut-down time for clean-up, food contamination and loss.
ii. Carbon Dioxide Systems -
The CO2 system is very similar to the Dry Chemical system except that the CO2 system has a damper in the duct designed to contain the gas, and the fan will be wired to shut down automatically upon actuation of the system. This system is a engineered total flooding system. CO2 systems must have class BC extinguishers nearby. The systems disperses the oxygen in the room, removing the fires energy.
*These are found in special application areas such as computer rooms that contain important documentation, museums, etc.
Pros:
-no clean-up problems, doesn't contaminate food, dissipates rapidly, and if there is a secondary supply of extinguishant the business can resume immediately after the problem has been corrected.
Cons:
-Being an engineered system it is expensive to install, and more expensive to recharge. There is IDLH problems that can occur if it trips in a confined space due to the depletion of oxygen.
iii. Wet Chemical System -
This system uses a liquid chemical called aqueous potassium carbonate; in which forms a soapy foam over the fire. The bubbles in the foam produce carbon dioxide which inerts the surrounding atmosphere. These systems must be hydrostatically tested every 12 years. Wet chemical systems must have class K extinguishers nearby. The wet chemical system cools the fire and removes the o2.
Pros:
-Pre-engineered which costs less.
Cons:
-Some Shut-down time, contamination of food, clean-up to be done.
Sprinklers:
Some buildings might extend their existing sprinkler system into an area of their cooking equipment as long as it meets both requirements of NFPA 13(sprinklers) and NFPA 96(fixed extinguishers). The heads will be SSP with approved special spray nozzles in which can discharge at intermediate, high, or extra high temperature rating. These heads must be replaced annually.
Checks/Tests/Inspections on the systems:
Storage Cylinder - Check the tag to see when it was last serviced (exception of CO2), and that the cylinder is as near as possible to the heads.
Control head - In operating condition, cable leading to the fuel shut-off.
Piping - Clear and free of grease build up
Detection - Free of grease buildup and links replaced annually
Heads - All required appliances protected, heads aiming in correct position, clean and free of grease build up.
Manual Pull Station - Located by means of egress, instructions on how to use posted, question employees to see if they know how to operate it, not obstructed
Hood - free of grease buildup
Filters - Listed type only, cleaned regularly, free of grease, in place
Cooking equipment - Proper clearances from fryer to open flame, minimum splash over to equipment or floors, and protected by a nozzle
Fuel shut off - In place? Is is approved? (i.e. manual reset)
