Fire smoke dampers are critical parts of passive fire protection systems that protect a building and its occupants. In order for fire smoke dampers to be effective, they need to be functioning properly. We’ve put together a list of the top 10 overlooked fire smoke damper issues.
- Inadequate access. Damper inspections involve having to operate the damper manually to prove the damper is actually functional. In order to do this, the damper must be accessible. The most common issue we see is that the access door is either installed too small, too far away, or no door is installed at all.
- Access on wrong side of damper. Spring loaded fire dampers have a locking mechanism that is only accessible from a specific side of damper. Fire/Smoke dampers have linkages and fusible links/resettable links that are only accessed from a specific side of the damper. The damper manufacturer has labels indicating which side to install the access door but is often still put in on the wrong side.
- Retaining angle not properly installed. This issue applies to fire dampers and combination fire smoke dampers. There are several different installation methods approved by the damper manufacturer in regards to retaining angle. These installation methods apply specifically to the manufacturer and model type. Common issues are insufficient number of fasteners used, improper use of single sided retaining angle installation method and no retaining angle installed.
- Incorrect opening location on the wall. This applies to fire dampers and combination fire smoke dampers. The centerline of the damper’s blades has to be installed within the plane of the rated barrier (wall). The damper manufacturer usually has a sticker on the sleeve indicating the proper location for it to be installed in the wall. When proper location in the wall is not achieved, this can cause an issue with the installation of the retaining angle. The fasteners used to attach the retaining angle to the damper sleeve usually end up penetrating the damper track and interfere with the operation of the damper blades and/or linkages. Every damper manufacturer has specifications as to how the damper opening in the wall is to be sized and constructed in direct relationship to the size and type of damper. This information must be provided by the HVAC contractor to the framing contractor.
- Items obstructing access. Various type of pipes, conduits, wire trays, wires and ducts obstructing proper access to damper. These could have been installed during construction or after occupancy.
- Improper selection of damper type. Common issue is using a standard damper type installed in a wall with a flush mount grille on one side. Doing this puts the centerline of the damper outside the plane of the wall and causes the retaining angle fasteners to penetrate the damper track. In this case the proper selection would be an “out of the wall” damper model that can be ordered with tabs to attach the grille.
- Smoke damper location to wall. Needs to be installed within 24” of the wall. Does not need to be installed within plane of wall but for new construction would be best practice.
- Field variations to the manufacturer’s approved installation methods. Variations are not acceptable except for in special circumstances. The AHJ (Authority Having Jurisdiction) must be provided an explanation of why the special circumstance exists, details of the variation and how this will not affect the functionality of the damper. Upon AHJ approval of the variation, documentation of the approval needs to be available for future inspections and provided with the final documents to the building owner for future reference. Without it, any variance to the installation is considered a deficiency.
- Improper Commissioning of Life Safety Dampers. Improper commissioning (also known as acceptance testing) is another common issue. Commissioning is usually completed by the HVAC installation crew, Fire alarm contractor and AHJ towards the end of the project before occupancy begins. At this point of the project, the AHJ is paying most attention to the fire alarm activation “functional testing” of the dampers and not necessarily verifying proper installation. The mechanical “operational testing” portion of the acceptance testing is usually provided by the HVAC contractor and any installation/operational issues should be flagged and remedied at that time.
- Electrical wiring not properly installed. A common electrical wiring issue is when the resettable reusable link (RRL) found on a combination fire/smoke damper is not properly field wired. This renders the fire protection function of the device useless. Another common issue is improper installation of the cover plate for the RRL which can also render the device useless.
Contact Metropolitan Mechanical Contractors to learn more!