A review of RR1218 - The effectiveness of witnessed four-stage clearances following licensed asbestos removal.

Early in 2025 the HSE released RR1218, a research report relating to the effectiveness of witnessed four-stage clearances following licensed asbestos removal.

The aims of this research were to:

• Assess whether the methodology used by four stage clearance (4SC) analysts during the 4SC process, including communications with the Licensed Asbestos Removal Contractors (LARCs), have improved; and
• Provide a measure of the extent to which industry practice now complied with HSE guidance (HSG 248), since HSE’s work on the Asbestos Analyst Inspection Program, 2015 (HSE publish 2018).

History & Context

RR1218 was one of three research reports completed by the HSE over the last three years. The series also include RR1217 -The use of control measures during licensed asbestos removal and RR1176 - Asbestos exposures to workers in the licensed asbestos removal industry.

The HSE research interrogated eight sites, comprising of 11 enclosures, where a variety of materials were removed, ranging from AIB, Sprayed Coatings, Insulation debris and pipe lagging between 2016 to 2019.

It is important to note, all clearances undertaken would have been completed to HSG248 Edition 1. Therefore, some of the findings and recommendations of RR1218 have already been superseded with the publication of HSG248 Edition 2 in May 2021.

 From the report the following findings were identified:

• Certificates for reoccupation (CfR), were issued at all sites but were not always clear unambiguous and accurate.
• Industry integration of HSE recommendations from previous work (HSE Asbestos Analyst Inspection Program 2015) was observed at five sites. Notably, the introduction of handover paperwork and the same 4SC company being employed during the lifetime of the individual removal projects, thus minimised the likelihood of a negative impact from using multiple analysts and / or analytical companies.
• An improvement in the application of the 4SC process was observed compared to previous studies (more failures were correctly identified).
• Reassurance air monitoring carried out by HSE scientists after stage 3 of the clearance process identified elevated fibre concentrations during or after enclosure dismantling. Reassurance air monitoring is currently optional in guidance and was not conducted by any 4SC analysts during the research.
• HSE guidance (HSG248) was not always followed:
• When selecting and using Respiratory Protective Equipment (RPE).
• When LARCs were required to undertake additional cleaning, analysts remained within the enclosure.
• When undertaking dust disturbance activities

Given that the context of RR1218 is based on the 2015 research HSE Asbestos Analyst Inspection Program, which was not issued to the industry until 2018, completed to HSG 248, Edition 1 standards and relates to sites assessed over the period of 2016-2019 - is it still relevant given the introduction of HSG 248 edition 2?

Overview

It did allow an overview of the current standards in the industry. It is also worth noting that all of the analytical organisations involved in the research were UKAS accredited and would have be inherently aware that along with the removal contractor and client, there were also HSE scientists present onsite overseeing the work.

Therefore, wouldn’t the analyst want to show their best work?

The Good

• There was obvious cooperation between the LARC and the Analyst, this was missing from the Asbestos Analyst Inspection Program.
• Clear reporting of failed areas. It had been previously highlighted that during the annual UKAS surveillance visits a large proportion of areas would fail, yet when reviewing historical information analytical firms have virtually no failures beyond this.
• The analysts did not undertake cleaning themselves during the assessment.
• Increased availability of information relating to fibre levels before, during and after works.
• Improvements  identified within the industry with a number of companies adopting changes highlighted in the original Asbestos Analyst Inspection Program.

The Bad

• Brushing air disturbance within the enclosure not completed for the minimum duration required.
• An analyst used a plastic bag for air disturbance. This has not been the accepted practice in the industry since HSG 248, Edition 1 was introduced.
• Removal equipment left in the enclosure area not bagged up prior to de-sheeting.
• CfR ambiguous with details lacking on drawings. It has to be questioned whether the specification of CfR report is too complex for the lay person to understand.
• Where a specific stage failed, analyst observed continued the clearance process at that stage rather than returning to stage 1.

And finally, the ugly

• Disparity between HSE recount of slides and the analyst original count leading to a passed area being subsequently failed.
• The report assumes that information from the initial Asbestos Analyst Inspection Program had been disseminated to all, prior to this project occurring. It is hard to say if this was the case.
• Although not undertaking cleaning, analysts observed remaining in the enclosure whilst major cleaning was being undertaken. It should be noted that even in the new analysts guide the necessity for the analyst to leave the enclosure is not required if minor cleaning activity is unlikely to exceed the control limit or the 10-minute level. At the time this was not a requirement of the standard.

Future industry improvements

While the asbestos analytical sector has seen notable improvements since the research, the consideration of the findings in RR1218 highlight several key areas requiring attention to both consolidate and extend our industries future progression.

Early and Consistent Engagement

The value of engaging analysts from project inception cannot be overstated. Including the analytical perspective early in the project lifecycle—at handover, during planning of removal works, and at every stage thereafter through to certification—ensures more robust planning, more reliable outcomes, and a shared understanding of project scope and limitations. This engagement coming direct from the dutyholder is key to ensuring a robust and transparent process able to deliver trustworthy assurances.

Clarity and Consistency in Reporting

Collaborative work in industry must be done to improve the CfR.  The report needs to be consistently clear, comprehensive, and unambiguous. This detail includes better site descriptions, annotated drawings, and clear documentation of failures and corrective actions. Whilst much of this can be improved with training for site analysts, the clearance templates (often laid out as documented in HSG 248), could be improved. These certificates ensure all required detail is captured, but all too often the technical level of these gives rise to difficulties in interpretation. The industry should consider the real-life end users of these documents, and consider if summary pages, with consistent information across the industry, would benefit end-users by improving the transparency and utility of clearance paperwork.

There is a need for better alignment of CfR with existing client held information on the asbestos containing materials (ACM) being remediated. This would include the client’s ACM references and space data room coding to enable the Duty holders to update their Management Plans and Registers more easily and accurately and record relevant caveats.

Protocols for Handover, Cleaning & Failure Management

The industry needs to move towards clear protocols for handover between Licensed Asbestos Removal Contractors (LARCs) and analysts. All too often analysts are asked to conduct a four-stage clearance knowing that it will ‘fail’ but using the analyst to independently confirm this. Such practice, knowingly puts the analysts (without licence and with different levels of proactive equipment) into situations where elevated exposure risks exist, and therefore is likely to breach the regulations. Proper documentation of failures, corrective actions, and the use of formal handover forms (as now required by HSG 248 Edition 2) should support a more structured, auditable process to reduce ambiguity over site status, and needs to be promoted amongst analysts, whilst being supported by the removal industry and the end-clients.

Training Discrepancies and Standards of Visual Inspection

The persistent gap between the LARC removal supervisor and site analyst training in relation to the ‘thorough visual inspection’ is a significant concern. The RR1218 review reports that sites where supervisors spent less time on visual inspections were more likely to fail subsequent analyst inspections. Fundamental to the regulations is the principal that the LARC is responsible for ensuring the asbestos is removed and area cleaned. The analytical process serves as a ‘double-check’, and to that end, the final visual inspection by the LARC site supervisor should be of the same level of detail and scrutiny and the inspection by the site analyst. Training for LARC supervisors must be brought into line with that for analysts if visual inspections are to be considered credible, with the methodology, duration, and equipment used, being in parity across the two parties.

Reassurance Sampling: Defining Best Practice

The role of reassurance air monitoring post removal requires better definition. Both HSG248 editions (1&2) indicate that reassurance sampling is “optional” and normally following an identified asbestos incident; in practice, this leaves room for considerable interpretation. The asbestos industry would benefit from a more consistent understanding of when and how reassurance sampling should be applied, particularly in the context of incidents. Currently, LARCs may request reassurance sampling even when no incident has occurred, while duty holders require it post-incident but before remedial action. The primary purpose of reassurance sampling should be clearly defined: to confirm a return to, or maintenance of, low respirable fibre content in the air. This includes providing clearer guidance on whether statements of cleanliness are appropriate within reassurance air monitoring certificates and identifying who is responsible for making these statements.

Consideration should be given to achieving a lower level of LOQ for such monitoring aiming for <0.005f/l or lower, this would then provide higher levels of reassurance to those reoccupying the area after asbestos disturbance.

Respiratory Protective Equipment (RPE): Uniform Standards

The ambiguity surrounding RPE use—specifically, how long RPE can be worn and the scientific rationale for recommended breaks—needs resolution. According to HSG53, non-powered RPE ‘should’ not be worn for more than one hour. However, this guidance documents the rationale for this; comfort, suggesting, not that the RPE would fail to protect if worn for longer, but that the wearer is more likely to move the RPE based on comfort after this duration. Both the use of the word ‘should’ and the rationale documented, leave considerable room for subjective interpretation. This risks inconsistent standards, undermines analyst safety and can cause conflict across workers, organisations and accreditors. Industry wide clear and uniform standards should be established to ensure the safety, effectiveness and consistency of RPE use.

The selection of suitable RPE should be a consideration for Analysts at the planning stage of the works and the Risk Assessment should be based on data form relevant previous personal monitoring.

Future Analytical Techniques

The review of fibre counting results using both PCM and TEM highlights the potential for significant discrepancies between the two methods. With discussions ongoing around potential future legislative changes to fibre counting accuracy, and subsequently the methodology, the industry must be prepared to adapt—potentially moving toward more widespread adoption of TEM or other alternative analytical approaches—as part of a continued drive for improved reliability and accuracy in asbestos testing. This is currently considered impractical and expensive, but as standards continue to evolve the industry must be prepared to look at how this could be done and what technological developments exist to facilitate transitions in the future, before the age-old method, becomes exactly that; old.

Conclusion

RR1218 is a valuable, if at times outdated, contribution to the evidence base underpinning the UK’s asbestos analytical sector. The report also serves as a reminder that the industry requires ongoing technical adaptation, and that the sector must guard against complacency in practice and training standards.

The asbestos analytical industry should be underpinned by a model of continual improvement: early engagement between all stakeholders, clarity and consistency in documentation, robust protocols for every step of the clearance process, and a willingness to embrace both new guidance and emerging analytical techniques. If the lessons of RR1218 are fully absorbed, the sector can continue to build on the progress already made in an everchanging world.