Fire Alarm Pull Station Installation Height
Are you in the field installing a fire alarm system and need to know what the required fire alarm pull station height is? Or maybe you are working on a fire alarm design detail and want to know what the required height is for your fire alarm call point. You’re not the first one to ask this question, so I will get right into it. What is the required height for a fire alarm pull station? The simple answer that the operable part of the pull station needs to be at least 42 in. (1.07 m), and not more than 48 in. (1.22 m), above the finished floor. Additionally, one pull station needs to be within 5 ft (1.5 m) of each exit doorway on each floor where required to be installed in a building. Both of these requirements are shown below. The code requirements NFPA 72®, National Fire Alarm and Signaling Code®, refers to a fire alarm pull station as a manually actuated alarm-initiating device, and defines it as a manually operated device used to initiate a fire alarm signal. Other publications may refer to a fire alarm pull station as a manual fire alarm station, pull station, fire box, call point, and so on. The requirements for the installation height can be found in Section 17.15 of the 2022 edition of NFPA 72. If you want to learn how you can easily find those requirements in the code using NFPA LiNK®, take a look at the video below. It’s important to note that NFPA 72 does not require that manual initiating devices be installed in buildings. Instead, it provides the installation requirements when the devices are required by other codes such as NFPA 101®, Life Safety Code®, NFPA 1, Fire Code, or NFPA 5000®, Building Construction and Safety Code®. Mounting the back box When mounting the back box for a manual pull station it is important to know the make and model of device that will ultimately be installed. As you saw above, the measurements are taken to the operable part of the device, not the middle of the device. Additionally, these measurements are taken from the finished floor, so when installing back boxes prior to the installation of the flooring, the thickness of the flooring must be accounted for in the measurement. Tolerances NFPA 72 allows a tolerance for the installation of devices. This tolerance is noted in 1.6.5 and A.1.6.5. Where dimensions are expressed in inches, it is intended that the precision of the measurement be 1 in., which would be plus or minus 1⁄2 in. The conversion and presentation of dimensions in millimeters would then have a precision of 25 mm, which would be plus or minus 13 mm. Therefore, the maximum height of the operable portion of the manually actuated alarm-initiating device could be up to 48.5 in. (1.233 m) if you account for the allowable tolerances in NFPA 72. Other wall-mounted appliance and device heights Do you want to learn more about installation heights for other fire alarm devices, appliances, and equipment? The video referenced earlier in this blog outlines how you can use the direct navigation feature of NFPA LiNK (NFPA DiRECT®) to find the mounting heights not only for fire alarm pull stations, but also for other wall-mounted fire alarm equipment, as well as all of the supporting code requirements.