Testing fire dampers annually – or more often in high risk and dirty/dusty environments – is a legal requirement. So, too, is acting on the outcomes if they fail inspection. As ever, planned prevention and maintenance is likely to be the safest and, in the longer term, the least costly option.
What might lead inspectors to fail your fire dampers or advise you that your installation is non compliant? What might be behind a ‘‘bad’ fire damper report?
Here are the main issues we see as fire damper testers for public and private sector organisations.
Maintenance
Mechanical damage and failure: Distorted or misaligned ducting or damper blades, corroded components and badly installed fastenings can all prevent a damper from being able to close.
Old and perishing fusible links and springs: Most fire dampers we inspect are spring operated and triggered by fusible links which are designed to melt at 72 degrees Centigrade. Both the link and the springs that close the damper must be in good order.
Dirty and clogged units: Grease and dust can build up to an extent that it will prevent a damper from closing fully. That’s why annual inspections should include basic cleaning of both faces of the damper – and why there need to be access hatches both sides. Consider more frequent inspection and cleaning in especially dirty and/or greasy areas (your risk assessment should already have picked up on that).
Deliberately disabled: Worst of all – and sadly not uncommon – are fire dampers that have been propped open to avoid “nuisance tripping”.
Non-compliant installation
Other issues can stem back to the original installation of fire damper installations. Common examples of such non-compliance are:
No access: To test a damper there needs to be adequate access to both test and provide photographic evidence that the damper can be closed and then reset. A lack of adequately sized access doors close to the damper is still very common.
The fact that that the original installers failed in their duty to provide access does not let you off the hook. Once aware of the lack of access, you need to arrange for access hatches to be fitted.
Other access problems include solid ceiling lack of builder’s hatches, cable tray and pipes obstructing access, lack of safe walkways in roof spaces and general lack of thought of maintenance needs when new ducting is installed.
Fire stopping: The fire-resistant seal around the duct as it passes through the fire-rated wall may have developed gaps. It should be visually inspected, and any concerns reported on as part of the inspection process.
Wrong fixing screws: Fire dampers must be installed in accordance with the manufacturer’s instructions. This includes a break-away duct joint connecting a fire damper to the attached ductwork. Fastenings must be of a non-fire-resistant material with a low melting point such as aluminium or plastic so that, if the duct expands in the heat a fire, the fixings melt and allow the duct to fall away from the damper. If the fixings are the wrong type, the damper could pull the duct out of the wall in a fire, compromising fire stopping between building compartments. It stands to reason that self-drilling steel screws should not be used.
Most of these ‘structural’ issues can be fixed by your competent testing specialist. Ideally, they will have an in-house fire damper maintenance and remediation team that will already know your premises and can prepare risk analyses and method statements quickly. They will also know your business and how best to arrange work around your day-to-day operations.
Find out more about Airmec’s comprehensive fire damper testing, repair, and replacement services.
_Published: 7 June 2023__
