The National Fire Codes (NFPA 25) and the GM Global (FM) Data Sheets (2-81) have both had substantial fire protection system updates in 2007. This would be an opportune time to see if your program properly reflects some of the latest basic items or if it is in need of an update. With this in mind, we hope to capture the current state of these documents for the most common elements – automatic sprinkler systems and fire pumps.
The FM change that will probably be of the most interest to those who try to follow their guidelines is the increase in sprinkler waterflow alarm testing frequency from monthly to quarterly. Rarely do we see a lessening of a fire protection system requirement, so this is probably a nice relief. Since many facilities use contract services for quarterly inspection of fire protection systems, this fits in nicely and relieves you of the need to use in house manpower for the previous more frequent tests.
Each sprinkler system has an alarm test feature – typically referred to as an “Inspector’s Test Connection” although there is an effort to have people start calling it an “Alarm Test Connection”. In wet pipe sprinkler systems, these are usually at the far end of the system. Other types of sprinkler systems (dry, preaction, etc.) have alternative features for testing and in some arrangements – typically high-rise buildings there is a “test & drain” combination at the control valve for sprinkler systems on each floor.
The purpose of the test is to simulate operation of a single sprinkler with the system in a normal state of readiness. What this means is that you should make sure the test connection terminates with an orifice of the same diameter as the sprinkler heads in the system. It also means that the normal state should not be altered by shutting off fire pumps that you may have installed.
A reasonable test flow time could be about one minute and in that time you should actuate your local audible alarm as well as any electronic signaling device for waterflow. Be sure to notify any supervisory facility prior to testing – failure to do so may have you welcoming the local fire department at your plant – a needless risk to them. Keep track of your tests and when concluded, quiz the supervisory facility as to what signals they have received – any missed signals should be double checked to make sure there is not a problem.
If you use a contract service for the testing, get a written document of the testing and review it for problems. Every now and then watch them perform the testing – you are paying for service and you want to be sure to get your money’s worth.
Sprinkler Control Valves
FM suggests all sprinkler control valves be locked and visually inspected weekly. For those valves that do not actually indicate the valve position by visual appearance, an additional “hands on” physical check should be conducted monthly. In addition, all of the valves should be fully operated – closed and reopened annually.
Other valves – usually small valves such as those controlling water to sprinkler system alarm devices should be checked for proper position – this could be done as part of the valve inspection program, or less frequently in conjunction with the quarterly alarm testing.
Fire pumps should be started weekly. If the pump is arranged for automatic start normally, start it that way for the test and let it run – about 10 minutes for electric drive pumps and 30 minutes for engine driven pumps. During this period, check general operation of circulation relief valves, pressure relief valves, and flow from packing glands – there are many other features that can be looked at during the run period that are not being enumerated here, but in sum the main thing is to make sure nothing is overheating and the pump seems to be running properly. Any abnormal indications should be checked out immediately.
While you are at it, check that pump room heat is maintaining about 40 F (70 F for engine driven pumps). If you have a suction tank, top it off and check the water temperature and heating system operation. Check the fuel supply for engine driven pumps – you want to keep the supply at least 75% full.
Keep records and include suction and discharge gage pressures, driver RPM, Amperes and for engine drives – oil pressure, coolant temperature, etc. Each week the readings should be compared to previous tests, looking for abnormalities or trends.
Perform a full flow test annually over the range of 0% to 150% of the pump rated flow and compare results with past testing. Conduct the test by flowing water – do not re-circulate pump discharge back to the pump suction line – even if this feature is part of your system. A recirculation flow can test the pump performance but does not include the status of the water supply to the pump.
Perform various maintenance tasks as suggested in the manufacturer’s literature and good common sense. Make sure the manual start feature is working properly on automatic staring pumps. Check the start/stop settings of jockey pumps and start pressure setting for the pump itself. Confirm pump is arranged for manual stop. Check pump supervisory alarm.
Dry Sprinkler Systems
Check air and water pressures each week along with valve room temperature. When it is really cold (below -20 F) make these checks daily. Check ball drips, accelerator or exhauster operability, compressors, and system low point drains monthly.
Perform a “dry trip test” annually using the Inspector’s Test Connection to expel air. Make note of the time to trip and the trip pressure. Increase in trip time from previous tests should be checked out. Every three years do a full “wet” trip – note the same data plus the time for water to work through the system and discharge from the test connection. You are looking for a 60 second maximum time. Check the quality of water for scale or debris, which can be an indication that a flushing investigation of the system is needed.
If your system uses non galvanized metal pipe you want to do a flushing investigation every 10 years in any event and increase this to every 5 years when the systems age past 20 years. Do this every 5 years from the beginning if you have an open water supply such as a pond or reservoir. If the system is galvanized, this is only required if you have an open water supply or there is a suspected problem.
Take good care of your fire suppression systems and they will do the same for your and your assets. There are other types of systems and individual facility arrangements that would expand or alter the above general guides. This is not meant to be a complete detailed outline. When Risk Logic visits your facility we will review your inspection and testing data for completeness and possible weak spots in the program. We will look for problems evident form the data. In addition, you can contact us at any time for assistance in developing an inspection, test and maintenance program for your specific facility situation.