Test preparation can be daunting for anyone, but with so many codes and regulations to know, getting ready for a fire alarm certification exam can be even more so. Here is a test-taking tip that should help you for years to come.
Pre-Test: For those thinking about taking an exam soon or those wanting to challenge themselves, consider that “90 seconds” appears 18 times in the Chapters of NFPA 72. Test yourself. Use the margins of this magazine or a separate sheet to list all of the rules you know of that will result in a correct answer of “90 seconds.”
One Question Three Different Ways
Here are three sample exam questions that address the same issue. Which would you prefer to see on a fire alarm system exam?
1. How would the lack of a waterflow alarm retard time affect local response of fire department(s) and why?
2. How long do you have before the building’s notification appliances sound after activation of the waterflow initiating device? 10 seconds, 20 seconds, 75 seconds, 90 seconds, 100 seconds.
3. True or false: NFPA 72 allows a maximum of 100 seconds before a waterflow alarm must be indicated at the FACP. T. F.
Of these questions, the first requires a deeper understanding of the dynamics and politics of fire alarm system false alarms and their consequences; the second is multiple choice – you can see the correct answer, and it may trigger your memory, but simply guessing will probably get you a failing grade. The true/false question gives you a 50-50 chance to just guess the correct answer, but those odds are still too long to rely on passing an important exam, and they are seldom used by licensing bodies.
Fill-in-the-blank and essay questions like the first one must be graded by hand, which opens up another can of worms, as it makes things more difficult for test givers and takers alike. Does spelling count? Are local terms or slang permitted? In the end, this analysis should help focus your preparation, as multiple-choice questions are clearly the all-around better way to construct a quiz for a wide range of subjects.
If multiple choice questions are going to be making up the majority of your alarm certification exams with various levels, then you should realize that it will be necessary for the ones making up questions to include every number (numerical value) they come across. These numbers will take the form of a distance, quantity, volume or unit of time.
Answering the Three Questions
Any essay answers for the first question should involve the cost to the municipality to operate trucks and emergency vehicles per run, the danger to firefighters while responding to an alarm, and the potential loss of life and property to the community when the fire department is delayed because they are out on another call.
For the second and third questions, it is important to notice that the question was asking for the time for activation of the notification appliances – not the activation of the waterflow switch itself. The switch must activate within 90 seconds; however, the FACP has 10 seconds to process and then indicate the alarm signal audible and visually. Thus, the answer is a total of 100 seconds – 90 seconds for a maximum retard setting, plus 10 seconds for the FACP to process the signal.
If you are disappointed in yourself, remember that each word in the question is important, and you must know what is being asked before you jump on an answer.
90 Seconds
Now you know that one instance of the use of “90 seconds” in NFPA 72 is for the maximum allowable time it may take for at least 10 GPM of water to flow from the smallest sprinkler head in a pipe branch before the waterflow switch is activated.
While I would not choose to answer “90 seconds” every time you see it on an exam, the sheer amount it is mentioned in the code should now be part of your test-taking knowledge. How did you do listing the 17 other places where “90 seconds” appears? Here’s the full list (code numbers are from NFPA 72, 2016 edition):
You can find three instances right away near the end of Chapter 10, “Fundamentals” in the section on supervisory signals:
10.13.1 Self-Restoring Supervisory Signal Indication. Visible and audible indication of self-restoring supervisory signals and visible indication of their restoration to normal shall be automatically indicated within 90 seconds at the following locations: (1) Fire alarm control unit for local fire alarm systems; (2) Building fire command center for in-building fire emergency voice/alarm communications systems; and (3) Supervising station location for systems installed in compliance with Chapter 26.
10.13.2.1 Visible and audible indication of latching supervisory signals shall be indicated within 90 seconds at the locations specified in 10.13.1.
10.13.2.2 Restoration of latching supervisory signals shall be indicated within 90 seconds at the locations specified in 10.13.1.
In the chapter on Inspection, Testing and Maintenance, table 14.4.3.2 indicates that during the initial acceptance test, and annually, supervising station alarm systems must have their transmission equipment checked. According to section 4(a): “Except for DACT, actuate initiating device and verify receipt of the correct initiating device signal at the supervising station within 90 seconds. Upon completion of the test, restore the system to its functional operating condition.”
Section 4(b) involves testing DACT line seizure capability. Part of that section requires you to verify each transmission attempt is completed within 90 seconds from going off-hook to on-hook. Later in NFPA 72, this 90-second rule is repeated in Chapter 26 (Supervising Station Alarm Systems) at section 26.6.4.1.3 called Requirements for DACTs: A DACT shall have the means to satisfactorily obtain a dial tone, dial the number(s) of the DACR, obtain verification that the DACR is able to receive signals, transmit the signal, and receive acknowledgment that the DACR has accepted that signal. In no event shall the time from going off-hook to on hook exceed 90 seconds per attempt.
This rule is also repeated in Section 27 of testing table 14.4.3.2, which indicates that during the initial and monthly acceptance tests, supervising station alarm systems must actuate [an] initiating device and verify receipt of the correct initiating device in 90 seconds.
Even the generic rules for “Performance-Based Technologies” – designed to cover any technology that is not addressed specifically in the code or invented yet – repeats the ubiquitous 90 seconds limit. Under section 26.6.3.8: The maximum duration between the initiation of an alarm signal at the protected premises, transmission of the signal, and subsequent display and recording of the alarm signal at the supervising station shall not exceed 90 seconds.
Section 17.12.2 (Sprinkler Waterflow Alarm-Initiating Devices) gives us the answer to our questions above: Activation of the initiating device shall occur within 90 seconds of waterflow at the alarm-initiating device when flow occurs that is equal to or greater than that from a single sprinkler of the smallest orifice size installed in the system.
Chapter 26, Supervising Station Alarm Systems, allows alarm signals from commercial fire alarm systems to be verified by the supervising station operator before calling the fire department, providing you comply with four provisions. According to the last provision of 26.2.2.1, the verification process (should) not take longer than 90 seconds from the time the alarm signal is received at the supervising station until the time that retransmission of the verified alarm signal is initiated.
Chapter 29 is similar, but applies to household fire alarm systems. 29.7.9.2 also allows operators to verify alarm signals prior to reporting them to the fire service, provided that the verification process does not delay the reporting by more than 90 seconds.
Supervising Station Alarm Systems section 26.3.5.2.3 applies to the supervising station facilities itself and not the protected premises when it says, in the event of the failure of equipment at the subsidiary station or the communications channel to the central station, a backup shall be operational within 90 seconds. This requires spare parts to be on hand for each brand and model receiver being used for monitoring commercial fire alarm signals.
Chapter 26 also has a “Display Rate” section (26.4.4.4) to make sure other signals coming in do not interfere with the prompt handling of the fire alarm signals sharing the same equipment if things get really busy. It says record simultaneous status changes at a rate not slower than either a quantity of 50 or 10 percent of the total number of initiating device circuits connected, within 90 seconds, whichever number is smaller, without loss of any signal whichever number is smaller, without loss of any signal.
The last three references are found in a less-used section of NFPA 72, which deals with two-way RF multiplex radio system reliability and its capacity to receive signals. The first reference in this section repeats the signal transmit time of the other means: The maximum allowable time lapse from the initiation of a single alarm signal until it is recorded at the supervising station shall not exceed 90 seconds.
The final two are found in section 26.6.5.2.2 – which allows a little wiggle room for the end-to-end operating time parameters for a one-way radio alarm system. Here, the hard-and-fast 90-second rule is bent a little with a probability and capacity rules added. Since these systems are one-way, there is no indication that the alarm was received by the remote station like there is with other methods, so the standard 90-second rule has been enhanced: There shall be a 90 percent probability that the time between the initiation of a single alarm signal until it is recorded at the supervising station will not exceed 90 seconds; in addition to the maximum operating time allowed for alarm signals, the system shall be able to record not less than 12 simultaneous status changes within 90 seconds at the supervising station.
Happy test taking!
Greg Kessinger has been SD&I’s fire alarm and codes expert and a regular contributor for more than 15 years. Email him your fire & life safety questions at [email protected].
