Fire dampers are a key component of a building’s fire safety system. While “active” components like fire sprinklers, regularly placed fire extinguishers, and alarms are critical in fighting a fire that has broken out, “passive” systems that work to contain the emergency are also a critical line of defense. Containment options include structural elements like walls, doorways and stairwells, as well as dampers placed within the ductwork. As stated in “What Engineers Need to Know About Fire & Smoke Dampers: A Collection of Technical Articles and the AMCA Guide for Commissioning and Periodic Performance Testing,” an international fire damper standardization guide, “[w]hen penetrating these walls or partitions by the ductwork of the heating, ventilation, or air conditioning (HVAC) system, the integrity of their ratings are sustained by the use of fire dampers, smoke dampers, or combination fire/smoke dampers.”1. Thus, it’s not enough to simply place any fire damper in an HVAC system. The fire damper selection and installation method, as well as maintenance frequency, must work to support the overall fire safety rating of the building or system (commonly, maintenance frequency is assumed to be once a year unless otherwise specified). The minimum fire safety rating is necessitated either by regional building codes or the particularities of the building’s use patterns and proximity to hazards.
Thus, like any key safety component, fire dampers must undergo a process of verification. This can be done using physical methods or remote methods. Physical methods have involved simulating actual heat or smoke conditions in order to trigger the mechanism that actuates the damper, but more frequently involve manually triggering the system using its controls. This is understandably difficult when dampers are placed in narrow or unreachable areas, and they frequently are, given their role in creating fire barriers that line up with external barriers such as thick walls. After this, it is sometimes necessary to replace single-use components such as fusible links.1 Predictably, because of this the industry is veering towards the use of remote methods due to their lower cost, lower risk, and compatibility with modern, digitally-controlled dampers. As stated by Esser and Vogel, “[o]ne cost-saving benefit of today’s combination fire/smoke damper design, which uses an electric actuator and an optional position-indicating device, is the ability to monitor and test the damper remotely.”1 These remote tests can include controlling the actuator motors to ensure they are in good working order, which conveniently involves only a control system command and not simulating actual fire conditions. As discussed by Esser and Vogel, the growing widespread use of digital maintenance testing has some surprising benefits; among them, the ability to maintain pathogen safety protocols when testing HVAC systems in hospitals. The decreased risk to the technician duly results in lowered costs to the hospital, which also encourages compliance with the recommended annual testing schedule even in the face of budget cuts and funding shifts. This represents a virtual win-win-win for the industry: lowered client costs, increased technician safety, and increased maintenance compliance.
It’s clear that fire damper verification continues to evolve as HVAC systems themselves become more digitized. What remains constant is the key role that dampers and other passive systems play in fire safety.