Workplace Dust Assessment

Who needs occupational dust evidence?

Sampling is relevant where work releases dust or disturbs deposited material. Typical settings include workshops, manufacturing areas, warehouses, maintenance zones and commercial premises where dusty work occurs alongside offices. The assessment may support a COSHH review, investigate a change in process, check controls after modification or establish exposure during a defined task. Office occupants without process exposure usually need an indoor particulate or deposit service instead.

Inhalable and respirable fractions

The inhalable fraction represents material that can enter the nose or mouth. The respirable fraction represents finer material capable of reaching the gas-exchange region of the lungs. The substance, task and assessment question determine which fraction is sampled. Where dust has a substance-specific workplace exposure limit, that limit and analytical method take priority over a general dust measurement. We confirm the required fraction before selecting heads, flow rates and laboratory analysis.

Personal sampling during representative work

A calibrated pump is worn by the employee, with the sampling head positioned in the breathing zone. Sampling covers a representative activity period and records the worker's tasks, materials, controls, breaks and unusual events. Pumps are checked before and after use, and samples are analysed gravimetrically by a laboratory. Static samplers or direct-reading monitors may be placed nearby to understand area patterns, but they do not replace the personal result when individual exposure is the question.

From task observation to interpretation

1. 1

   Define the exposure group

   Agree workers, tasks, substances and control measures that the samples must represent.

2. 2

   Review the work

   Observe duration, material handling, extraction, enclosure, housekeeping and respiratory protection.

3. 3

   Collect personal samples

   Use the correct inhalable or respirable sampler through representative activity and record deviations.

4. 4

   Compare with EH40

   Interpret the laboratory mass against the applicable workplace exposure limit and sampled duration.

5. 5

   Set proportionate actions

   Identify control, maintenance, further substance-specific analysis or repeat sampling where justified.

What the assessment can and cannot conclude

The result estimates exposure for the sampled worker, task and period. It can indicate whether current controls produced exposure below or above the relevant comparison criterion during that work. It cannot represent every shift, worker or process condition without a sampling strategy designed for that variation. A general gravimetric result measures mass; it does not identify all constituents. Where toxicity depends on composition, the substance must be sampled and analysed specifically.

Control actions and occupational programme support

Recommendations follow the hierarchy of control and may address substitution, enclosure, local exhaust ventilation, methods, housekeeping or respiratory protection. Mechanical or LEV faults go to the appointed competent contractor. Hazardous Substances Monitoring is the appropriate route where the client needs a wider programme covering several agents, exposure groups or control-verification activities.

Is this the right page?

Choose this page for personal inhalable or respirable dust exposure under COSHH. For a broader occupational hygiene programme, use Hazardous Substances Monitoring. For office PM trends without a process-exposure question, use PM2.5 and PM10 Office Monitoring.