How to read an asbestos test report
“No Asbestos Detected” (NAD) means the analyst found no asbestos fibres in the sample examined. To understand what that means for your building, read across the same row of the certificate. Which material was tested, where was it taken from, and is that the material your contractor is about to disturb?
What does a bulk analysis certificate look like?
An ASM bulk analysis certificate has two parts. The first page identifies the job, the client and the number of samples received. The second gives each sample its own result. The worked certificate shows two sample rows: a Room 01 panel recorded as NAD and a roof sheet fragment recorded as positive for chrysotile.
In this worked example, Ben Pickard is listed in both “Sampled By” fields. EX-01 is the Room 01 panel. Both pages below are adapted from an actual ASM bulk sample certificate for teaching. The two-sample count includes one fictional positive example. The client, surveyor entry, references and sample descriptions have been adapted for this worked example. Use the numbered arrows and key, or expand either page for a closer look.
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Show numbered key for page 1
- Project reference. EX-JOB-01 links the cover and results sheet.
- Sample count. Two rows are shown in this worked example.
- Client. The organisation commissioning the work.
- Client address. The correspondence address.
- Site address. The property where sampling took place.
- UKAS number. 32982 is the laboratory accreditation number shown on the certificate.
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Show numbered key for page 2
- Laboratory sample number. EX-01 and EX-02 identify separate samples.
- Client reference / sample ID. DEMO-B is the fictional client reference for EX-02.
- Location and material. EX-02 represents a roof sheet fragment in a store cupboard.
- Material classification. The illustrative second sample is a cement product.
- Asbestos identified. Chrysotile is the fibre type in the fictional positive example.
- Result code. EX-01 reads NAD. EX-02 shows a detection.
Compare the two results on page 2
EX-01 · NAD. In this worked example, no asbestos is detected in the Room 01 panel sample.
EX-02 · Chrysotile detected. This fictional roof sheet sample illustrates a positive finding. The fibre type describes the material tested. Airborne fibre concentration requires a separate measurement.
How do you read the result row?
Start with the sample reference. Match it to the sampling record, photograph or marked-up plan. If two panels are recorded in the same room, the room number alone may be too broad to identify which one supplied the sample.
Read the material description and classification together. Here, the item submitted was a fragment of the Room 01 panel. “Panel” describes the kind of material. The separate result column tells you what the analyst found. “No Asbestos Detected” and “NAD” are two ways of recording the same finding.
Check the issue number and notes. If the laboratory has reissued the certificate, use the current version. Read any comments alongside the result. Where a customer supplied the sample, the location on the certificate may come from the customer’s label. Ask the person who took the sample if that description is unclear.
Does NAD apply to every panel in the room?
The laboratory finding applies to the panel fragment examined. Imagine the contractor is replacing a second panel on the opposite wall. Even if the two look identical, the certificate alone cannot tell you whether the second was fitted at the same time or made from the same material. Check the survey and sampling record to see what the surveyor considered the sample to represent. If the second location remains uncertain, leave the material undisturbed and ask a competent asbestos surveyor to review it before work starts.
What if the report says “trace” or names a fibre?
The reporting notes on the example certificate allow the analyst to record TRACE when only one or two fine asbestos fibres are identified. That records a detection. A named result such as chrysotile identifies the type of asbestos found. Neither entry gives an airborne fibre concentration. If the wording affects planned work, give the full report and work description to the person assessing the risk.
How did the laboratory examine the sample?
The certificate records that the analyst used polarised light microscopy and dispersion staining. These techniques help identify fibres in a piece of material. Measuring fibres in the air answers a different question and requires air sampling. HSE describes the bulk identification method in Appendix 2 of its analysts’ guide. Read HSE’s Analysts’ Guide (HSG248).
Have a certificate you need help reading?
Give ASM’s Sunderland laboratory the project number, sample reference and exact wording you want to check. If you are planning work, describe where it will take place and what material it will disturb. That helps the team identify whether your question concerns the laboratory finding or the survey coverage.
ASM bulk sample testing in Sunderland · HSE guidance on choosing an analyst or surveyor
