FM200 fire suppression system which is also well known as HFC227ea Fire suppression system is one of the most effective clean agent fire suppression system as an alternative to a fire sprinkler system. Not only that the room is protected from the damage or spread of fire but most importantly the equipment which is very high in value, critical to business operation and continuity, is safe from damage and operational even after a fire event.
It is therefore very critical for fire protection designers to decide when this type of fire suppression system should be required. HFC227ea fire suppression system is very effective as an extinguishing agent for Class A, B & C types of fire if the required minimum design concentration can be achieved considering factors that affect its effectiveness such as the number of tees, bends in the layout, room leakage, room height, elevation, ambient temperature & cylinder location are kept within the limit of manufacturer.
Compare to Halon which is banned from production due to its impact to ozone layer & un-acceptable global warming potential, the HFC227ea is considered as “ZERO” ozone depletion with little & acceptable global warming potential. With the advantage of odorless, non-conductive & leaves no residue after discharged & not risky to people compare to other alternative like CO2 & inert gas (which reduces oxygen level until complete control of fire is achieved), this agent is mostly used by designers as alternative for fire sprinkler common in data centers, server room, electrical room, clean room & Telecommunication room. Designers need only to always check the limitations with the manufacturer and ensure that the HFC227ea is not used in some applications which it is not permitted to use.
HFC227ea Fire suppression system is divided into two main components, one is "Mechanical", and the other is "Electrical".
Mechanical components are the pipe, fittings, cylinder rack, agent cylinder, HFC227ea agent, cylinder rack, nozzle, discharge valve head, liquid level indicator, pneumatic actuator, pressure gauge, manifold, non-return valve & signage.
FM200 fire suppression system Mechanical components
Electrical components are fire extinguishing control panel, detector, manual release station, abort switch, electric actuator, low pressure switch, discharge pressure switch, audible & visual notification appliances, main-reserve switch, auto-manual switch & other fire safety control interface.
FM200 fire suppression system Electrical components
HFC227ea Fire suppression system operates in two modes. It can be operated either manual or automatic.
In manual mode, the activation of fire suppression system can only be achieved with human intervention. When a confirmed fire is determined at protected area, the manual release station must be activated to discharge the extinguishing agent. Upon activation, the extinguishing control panel change to release mode, activate the audible & visual notification appliance, activate internal panel buzzer, activate other fire safety control such as control of motorized damper, a/c shutdown & de-activate door access control. Release agent to the protected area without time delay, alarm & release LED illuminates. Designer shall ensure that in manual mode, the recommended minimum design concentration as per manufacturer shall be used.
In automatic mode, the release of agent can be operated at two ways. One is if two detector is activated in cross zone arrangement, the extinguishing control panel change to alarm mode, alarm LED lit, activate the audible & visual notification appliance, activate internal panel buzzer, activate other fire safety control such as control of motorized damper, a/c shutdown, de-activate door access control & countdown timer starts. Once time delay elapsed, agent release to the protected area and release LED illuminates. Other way to release the agent is to activate manual release station. Once activated, the extinguishing control panel change to release mode, activate the audible & visual notification appliance, activate internal panel buzzer, activate other fire safety control such as control of motorized damper, a/c shutdown & de-activate door access control. Release agent to the protected area without time delay, alarm & release LED illuminates.
Be noted that the release of agent can also be delayed when it is determined that the cause of alarm activation is false or when the fire is extinguished at early stage by using other media like fire extinguisher. To do this, the abort switch shall be activated. Once activated, the countdown timer reset and stop. When abort switch is released, the timer starts and the operator have 30 seconds (depend on agreed time delay) to leave the protected area, reset the extinguishing control panel and to completely return the system to normal mode.
4. How to do Commissioning and Maintenance FM200 fire suppression system
Commissioning
In preparing the system for commissioning, engineers must ensure that the required documentation of the system like the approved as-built plan, battery/voltage drop calculation, record of completion, components & panel checklist are available and must be filled up, signed, and submitted to client for records. Before the approved scheduled date/time of test, the assigned project engineer must ensure that the scheduled test is completely announced to the occupants within the facility by coordinating with the client. The engineer should coordinate with the testing and commissioning engineer & certified technicians who will be assisting him throughout the test. Ensure that the other fire safety-controlled equipment such as security access-controlled door, A/C and motorized damper are all operational and ready for test. Engineer must see to it that the area to be tested has passed the room integrity test as per NFPA 2001 requirement before the test.
During the schedule date of test, ensure that all the required witness like client, consultants, contractor, and other sub-contractor required for the test are present to successfully complete the test. Check that the system (electrical & mechanical components) is normal prior to the test. Ensure that the electric actuator is detached from the agent cylinder to prevent accidental discharge. When everything is checked and found all normal and ready for test, the following must be observed and completed in sequence:
Alarm & Trouble Test
1. Activate one detector from any zone using listed smoke canister. Don’t test by magnet as it is not recognized by NFPA 72 as correct method. Observe the LED from detector if it changes state.
2. Extinguishing panel “Alarm” LED illuminates.
3. 1st Stage audible/visual notification appliance activates.
4. Countdown timer is OFF.
5. Panel buzzer sounds.
6. Remove the detector from its base, check if the Trouble LED illuminates.
7. Return the detector to its base, observe if the trouble led automatically restore to normal.
8. Press “Silence” and acknowledge button. Observe if the audible/visual notification is de-energized.
9. Press “Reset” button. Observe if the panel restores to normal condition.
10. Repeat test to all detectors.
Supervisory Test
1. Activate low pressure switch by connecting jumper to its two wires or if test button is available.
2. Extinguishing panel “Supervisory” LED illuminates.
3. Panel buzzer sounds.
4. Remove one wire from its connection. Check if the Trouble LED illuminates.
5. Return the wire. Observe if the trouble led automatically restore to normal.
6. Press “Silence” and acknowledge button.
7. Press “Reset” button. Observe if the panel restores to normal condition.
Discharge Pressure Switch Test
1. Activate discharge pressure switch by connecting jumper to its two wires or if test button is available.
2. Extinguishing panel “Release” LED illuminates.
3. All audible/visual notification appliance activates.
4. Panel buzzer sounds.
5. Remove one wire from its connection. Check if the Trouble LED illuminates.
6. Return the wire. Observe if the trouble led automatically restore to normal.
7. Press “Silence” and acknowledge button.
8. Press “Reset” button. Observe if the panel restores to normal condition.
Release Mode (Automatic) Test
1. Activate one detector from any zone using listed smoke canister. Don’t test by magnet as it is not recognized by NFPA 72 as correct method. Observe the LED from detector if it changes state.
2. Extinguishing panel “Alarm” LED illuminates.
3. 1st Stage audible/visual notification appliance activates.
4. Countdown timer is OFF.
5. Panel buzzer sounds.
6. Activate second detector from another zone. Don’t test by magnet as it is not recognized by NFPA 72 as correct method. Observe the LED from detector if it changes state.
7. 22nd Stage audible/visual notification appliance activates.
8. Countdown timer is ON.
9. Close motorized damper.
10. De-activate security access-controlled door.
11. Shutdown a/c.
12. After time delay elapsed, RELEASE LED illuminate. Audible/visual notification device installed outside protected area activates.
13. Electric actuator activates. Verify its physical appearance to confirm activation.
14. Press “Silence” and acknowledge button.
15. Press “Reset” button. Observe if the panel restores to normal condition.
Release Mode (Manual) Test
1. Activate manual release station.
2. Extinguishing panel “Alarm” and “Release” LED illuminates.
3. All audible/visual notification appliance activates.
4. Bypass countdown timer. No delay.
5. Panel buzzer sounds.
6. Immediate activation of electric actuator. Verify its physical appearance to confirm activation.
7. Press “Silence” and acknowledge button.
8. Press “Reset” button. Observe if the panel restores to normal condition.
Maintenance
In maintenance of the HFC227ea fire suppression system, it is always recommended for engineers/technicians to always follow the manufacturer’s recommendation which can be found at the installation & operation’s manual or according to NFPA 72. The frequency of visual inspection, maintenance and test shall be performed in accordance with minimum requirement of NFPA 72 as follows:
1. Inspection of extinguishing panel fuses, LEDs, primary power supply & trouble signals. (Weekly)
2. Inspection of battery (Weekly)
3. Inspection of initiating devices such as detector, manual release station, abort switch etc. (Semi-annual)
4. Inspection of other fire safety control interface (Semi-annual)
5. Inspection of audible & visual notification appliance (Semi-annual)
6. Testing of Extinguishing panel & modules functions, fuses, LEDs & power supply (Annually)
7. Testing of Extinguishing panel trouble signals for audible/visual notification, disconnect switches & ground fault (Annually)
8. Testing of battery (Annually)
9. Testing of initiating devices such as detector, manual release station, abort switch etc.
(Annually)
10. Inspection of other fire safety control interface (Annually)
11. Inspection of audible & visual notification appliance (Annually)
Design of HFC227ea fire suppression system shall be made in accordance with the minimum requirements of NFPA 2001, NFPA 72 and manufacturer’s recommendation. Design of FM200 basically starts with identifying what type of hazard are we going to protect, room ambient temperature & elevation. Once the type of fire hazard is known of which class, the minimum design concentration can now be determined considering the room ambient temperature and elevation reference to sea level. It must be noted by designers that every raised floor and compartment if not separated by wall shall be considered in the protection as also stated in NFPA 2001.
The spacing of detector shall be in line with the recommended spacing of manufacturer or as per NFPA 72 considering coverage area for air change per hour. This is critical especially in rooms with high air velocity where smokes from fire becomes diluted before it enters the detector smoke chamber and therefore lessen its effectivity.
Placement of abort switch and manual release is recommended to be even. Meaning, you should locate abort switch too in location where manual release is installed. Audible and visual notification shall be provided inside and outside protected area as per NFPA 2001. Abort switch must be located inside the room while manual release is located outside.
Location of extinguishing panel must be located near to the entry door and outside protected area. Storage area for agent cylinder must have operating temperature within 20-54 deg Celsius as recommended by most manufacturer. Cylinder is recommended to be as close as possible to the protected are or within the limit of manufacturer which can be easily identify especially when hydraulic flow calculation is available.
Use 6.7% minimum design concentration for Class A and 7% for Class C, and minimum 8.7% for Class B(Heptane) or as per the recommended concentration for other flammable liquids as per manufacturer. Normally occupied space shall have design concentration up to 10.5% while not normally occupied can be more than this concentration provided that the acceptable maximum human exposure time is not exceeded by providing enough time for people to evacuate which can be done in setting countdown timer.
To achieve the minimum design concentration, other required fire safety control must also be taken into consideration in the design like a/c shutdown, closing of motorized fire smoke damper and latching of door and de-energized security access-controlled doors.
With all the above parameters considered and possible additional requirement from site depending on what equipment and services we have in protected room, we can assure that our design will work as intended which is to minimize property loss from fire, life safety & health safety.