Construction health guide

What to do when construction dust extraction stops working

If on-tool extraction is a planned control and it stops capturing construction dust, stop the dust-producing operation, keep other people out of the affected area, and find out why the control failed. Do not keep cutting or grinding on the assumption that a mask alone makes the original method acceptable.

Correct the fault or choose another assessed method that controls exposure, check that the control actually works in the task conditions, brief affected workers and record the decision before restarting. HSE says on-tool extraction is a type of LEV made of the tool, hood, extraction unit and tubing, and each part affects control. If suspected asbestos-containing material is discovered or damaged, stop and follow the separate asbestos emergency procedure with specialist advice. HSE: on-tool extraction, CIS69; HSE: construction dust FAQs.

Why a small fault can change the whole assessment

“Cut blocks using on-tool extraction and suitable RPE” assumes the extraction actually captures the dust. A detached hose, blocked filter, damaged shroud, full collection bag, mismatched connector or failed power supply removes that protection while the work looks superficially unchanged. Construction dust can include respirable crystalline silica from cutting, drilling or grinding concrete, brick, stone or mortar. Fine respirable silica is too small to see in normal lighting, so an apparently clear area is not proof of adequate control. The risk is not limited to the operator: nearby workers, cleaners, visitors and occupants of adjacent areas may encounter dust that escapes the work zone. HSE: silica and construction.

Recognise the failure early, then stop and secure the area

Warning signs: dust appears where capture was expected; an airflow indicator or alarm changes; a hose slips, collapses or leaks; a filter alarm sounds; a bag is full; the shroud no longer sits correctly; the tool is changed but the old hood is retained without checking compatibility. Stop the cut, grind, chase or sand producing uncontrolled dust, make the tool safe, keep people away, and tell the supervisor and any other trades sharing the space. Do not ask the operative to finish “just two more cuts”. A short job can produce a high concentration, and the failure has removed the condition on which the method was based. Do not start dry sweeping or compressed-air cleaning as an improvised response. HSE: scabbling or grinding.

Find the failed link in the control chain

Following the manufacturer’s instructions and safe isolation, check the simplest observable causes first: is the right unit connected and running; are the tool and unit compatible; is the hood fitted and positioned to capture at the cutting point; are hose connections tight and the path unobstructed; is the filter serviceable; is a bag full? The fault may be in the method rather than a broken part. A plunge cut, unusual angle, high dust-generation rate or changed material may overwhelm a setup that worked before, or a worker may remove a shroud to see the cut line. Do not label a system “repaired” because the motor restarts; compare its performance with the control specification for this task, and remove genuinely faulty equipment from use.

Decide whether the work method can change

The best recovery may be to eliminate or reduce the dust-producing operation, for example materials supplied cut to size, a block splitter, or moving the task to a controlled location. If the method still generates dust, select an effective source control and check the whole system fits the tool and task. Water suppression may be an alternative for some tasks but must deliver enough water continuously at the point of dust generation; wetting the ground beforehand is not equivalent. Do not make a substitution by writing “use mask instead” on the permit. RPE is often an additional control, needs the right type, fit and wearing conditions, and HSE says employers should not normally rely only on PPE unless they can justify it. HSE: construction health-risk control.

Check the people affected, then verify before restart

Ask how long the uncontrolled task ran, what material was worked, who was close by and whether dust may have travelled into an adjacent workplace. This helps choose immediate controls and whether a competent occupational-hygiene assessment is needed, but it does not allow inferring a precise dose from visible dust. A safe restart is an observed condition, not a signature alone: confirm the task, material and tool match the revised assessment; check the hood captures at source, the hose is intact and connected, and indicators behave as expected; run a controlled initial operation and observe whether dust escapes. Visible dust is a useful warning, but its absence cannot demonstrate that respirable silica is controlled. Define who authorises restart and record the equipment ID, defect, remedy, verification, people briefed and time work resumed. HSE: construction exposure monitoring.

FAQs

Can we continue with RPE while the extractor is repaired?

Do not assume so. HSE recognises RPE as an additional or sometimes necessary control, but employers should not normally rely on PPE alone without justification. The answer depends on the material, task, people affected and whether another effective source-control method is available, so pause and get competent advice before changing the method.

Does a current LEV test report mean a capture fault is not our problem?

No. A report records a competent examination at a point in time; day-to-day use still requires the system to work. HSE guidance calls for regular signs-of-damage checks and repairs, and the user and employer should act when the current setup visibly or otherwise fails.

Is visible dust the only restart test?

No. It can reveal obvious failure, but the finest respirable particles may not be visible. Verify the whole control setup and consider competent performance or exposure monitoring if the risk and uncertainty warrant it. Absence of a cloud does not establish compliance with an exposure limit.

Should every failure trigger health surveillance?

No universal rule follows from one equipment fault. Review the substances, exposure pattern and existing occupational-health assessment with competent advice. Health surveillance is a planned process for certain health risks, not a retrospective measurement of one event.

Where Complys fits

Complys offers task-specific RAMS and COSHH assessment workflows and document/review management, which can help document the intended controls, a revised method and a review date after a control failure. It does not sense airflow, triage faults, measure exposure or approve a restart. Verify the physical controls on site with competent people.

COSHH assessments →Construction compliance →