Regulator steps in after ‘Achilles heel’ warning on smoke dampers

The government’s product safety regulator is carrying out a review into smoke control dampers, after an industry body said faulty installation may be an “Achilles heel”.

Smoke control dampers are used to automatically prevent the spread of smoke through a building via dynamic air systems such as air conditioning and ventilation.

While a fire damper activates if the duct temperature reaches a high enough level to melt a fusible link, a smoke damper closes if smoke is detected. Building owners are responsible for arranging damper inspections.

The Office for Product Safety and Standards (OPSS) said: “Some manufacturers, importers or distributors of smoke control dampers are being contacted to provide documentation which includes, but is not limited to, declarations of performance.

“OPSS aims to provide targeted, risk-based and proportionate enforcement of construction products regulations and will act fairly and firmly where product risks exist.”

The investigation has been launched after the regulator was briefed by the Building Engineering Services Association (BESA). Several BESA members have reported incorrect and potentially unsafe installation of fire and smoke dampers.

To address the lack of a defined standard, BESA produced technical bulletin VH001 in March 2021 (updating it in August 2022) as best-practice guidance for testing smoke dampers.

BESA expects to replace VH001 by the end of this year with DW145 (‘BESA Guide to Good Practice for the Installation of Fire and Smoke Dampers’).

The damper safety issue “has been relegated down the agenda but is still very important to us in BESA”, its president Rab Fletcher told Construction News. “Has the sting fallen away from it? Maybe slightly but the issue isn’t going away.”

In 2022, BESA also raised the alarm over what it called “a huge number” of incorrectly installed fire dampers with self-drilling tek screws that would not melt in a building fire, thereby not triggering the release of spring-loaded dampers to contain a blaze.

“Grenfell exposed the broad problem,” noted BESA communications consultant Ewen Rose. “Fire dampers are a good example of ‘out of sight, out of mind’, because you only ever need them in an emergency. Most people in buildings didn’t know they had fire dampers, certainly didn’t know how many they had and certainly didn’t know the last time they’d been serviced.”

Fletcher noted that some dampers were installed up to 30 years ago. “Now the push is back on to get them serviced, especially in larger buildings.”

Testing, instrumentation, research and consultancy organisation BSRIA calculates that 300,000 dampers are made and installed in UK buildings each year.

Regular inspections of fire dampers are mandated by law but even with building safety so clearly in the public eye, there is a shortage of qualified staff.

“There’s no way that even 10 per cent of the installed fire dampers are being inspected regularly,” Rose noted. “It’s difficult to get access to the dampers and there aren’t enough inspectors to cover 100 per cent.

“It’s a very serious issue, and we were making progress pre-Grenfell. But Grenfell has raised consciousness of fire safety, not just for cladding but other safety measures too.”

BESA technical director Graeme Fox said that manufacturers’ instructions for correct installation are often confusing.

“For example, some clearly state that you should not use self-drilling, non-fusible fixings, but some are not so clear,” he said. “We briefed the OPSS about this problem and they have now informed us that they are contacting manufacturers and importers to ensure there is clarity and consistency in their declarations of performance.”

The OPSS is empowered to remove products from the market if they prevent a safety risk. It can also prosecute or fine businesses that break product safety rules.