Environmental sampling of asbestos may be required for various reasons including identification of a source of contamination, assessment of personal exposure, determination of background levels and to check the efficiency and effectiveness of control measures. Decisions about the potential risk of exposure, the compliance or otherwise with control limits, action levels and the clearance indicator level are dependent on air sampling and analysis. It is essential therefore that those measurements are competently carried out using the appropriate sampling procedures and equipment.
Environmental & Site Safety Solutions Limited (ESSS) is UKAS accredited and committed to providing reliable asbestos site sampling and testing services to ISO 17025 standards and for ensuring the correctness and reliability of sampling and testing. To achieve the level of competence to enable continued compliance ESSS will:
- Use technicians who are adequately trained to perform sampling and testing
- Provide suitable laboratory accommodation, ensuring that acceptable environmental quality for the analysis of test samples is maintained
- Use sampling and testing methods as described in HSG 248
- Use equipment of established design that is suitable for the specific test activity
- Maintain equipment calibration programmes
- Handle samples using methods described in HSG 248
An air sampling strategy will be devised prior to asbestos remedial works to ensure that all aspects of the work are covered. Technicians employed by ESSS to carry out asbestos air sampling and analysis will use any of the following sampling applications depending on the client's specification and scope of works:
Background sampling is conducted to establish ambient airborne fibre levels prior to the commencement of any activity that may lead to airborne asbestos contamination.
Leak (Enclosure Check) Testing
Sampling outside an enclosure and in adjacent areas during the removal process to ensure that effective fibre containment is being maintained.
Site Clearance Certification for Re-occupation
Site clearance certification is carried out once removal and/or encapsulation of the asbestos specified has been completed. The four successive stages of site clearance certification are:
a) Preliminary check of site condition and job completeness
b) Visual inspection inside enclosure or work area
c) Clearance air monitoring
d) Final assessment of site for reoccupation after enclosure/work area dismantling
ESSS will organise clearance testing and the issue of site certification for re-occupation (must be accredited by UKAS to do so).
This type of monitoring may be required in certain circumstances (such as when an enclosure has been dismantled on completion of asbestos removal) to confirm that the residual asbestos airborne fibre concentrations are less than 0.010 fibres per millilitre of air sampled.
This type of test is to be carried out when it is necessary to assess the exposure level of an individual carrying out his/her work. Sampling of asbestos removal personnel working in enclosures to ensure that adequate respiratory protective equipment is worn (referred to as an RPE test) or sampling to check compliance with Control Limits under the Control of Asbestos Regulations 2012 are examples where personal sampling is applied.
Work Area Sampling
This type of sampling is to assess the release and spread of asbestos fibre concentrations near sources (e.g. inside enclosures, work without an enclosures) The results can help determine whether the control measures in place are effective and suitable and give removal contractors the peace of mind that the expected exposure is not being compromised and also gives another measurement for their health surveillance program.
Sampling Certification and Reporting
Normally, all air sampling certification is prepared on-site and issued by the Technician. Where required, a daily written report is produced detailing airborne fibre monitoring activities and occurrence of any events related to the project. This provides the client with an ongoing detailed record of the progress and extent of asbestos remedial works.