P404 Clearance Testing and the Requirements of a Certificate for Reoccupation

The P404 is one of two air monitoring qualifications recognised within the asbestos industry and covers four stage clearance testing and issuing of the certificate for reoccupation.

British Occupational Hygiene Society logo

Our P404 course

For asbestos removal and remediation projects, an independent asbestos analyst should be employed to conduct a thorough clearance inspection of the site. This is to check that control measures are effective, asbestos materials have been managed accordingly (removed / encapsulated / repaired), and method statements have been followed. There is also a legal requirement for asbestos analysts to undertake formal training in their role, as outlined in the Control of Asbestos Regulations (CAR) 2012, Regulation 10, and HSG248: Asbestos: The Analysts’ Guide.

The P404 qualification gives you the skills and knowledge required to thoroughly and safely undertake all four stages of the clearance process. It also teaches you how to identify any outstanding asbestos risks, and how to issue a certificate for reoccupation when you are satisfied the site is safe to re-occupy.

Why choose Asbestos Management Services?

Our dedicated team of experts have a wealth of experience conducting air monitoring activities across a large and varied estate. We train our own staff to successfully pass the P403 and P404 qualifications and are experts in all areas of air sampling, fibre counting and clearance monitoring. We have many years of experience working on both large and small removal / remediation projects, associated with public buildings including extensive education stock, where SCOLA and ROSLA system buildings are prevalent.

As a non-profit organisation, we hold quality at the heart of everything we do.

In addition to our highly qualified asbestos training providers, we also have a support team available via phone or email. With Asbestos Management Services, you will always receive the highest levels of training and support.

Who is it for?

The qualification is suitable for anyone who is:

  • undertakes clearance inspections and air monitoring of asbestos as part of their work (e.g. asbestos site analyst)
  • issues certificates for reoccupation following asbestos clearance procedures
  • undertakes airborne fibre counting and requires an understanding of the external processes used in air sampling
  • manages asbestos site analysts

Level of Qualification

This is a level 4 qualification in the BOHS qualifications framework, equivalent to NVQ Level 4 and HNC.

How is it Delivered?

The P404 course will require at least 11 hours of study time, of which at least 9 hours will be taught (teaching and practical assessments) and 2 hours will be independent (in your own time). In addition, there will be 4 hours of examination time.

Content / Learning Outcomes

Overall Aim - To provide you with the theoretical knowledge and practical ability to undertake all four stages of the clearance test including that of the decontamination unit (DCU) and the issuing of a certificate for reoccupation and a DCU clearance certificate.

Learning Outcomes - On completion of this module, you will be able to demonstrate the correct method for:

  • Understanding and accurately assessing all four stages of the clearance process
  • Identifying when faults are present and providing direction to the licensed contractor to rectify them
  • Understanding and utilisation of all safety controls including use of RPE/PPE and personal decontamination
  • Collecting and recording suitable and sufficient contextual information and photographs in order to provide comprehensive certificates for reoccupation and clearance certificates for DCUs

The P404 covers eight main topics:

  • Role of the Analyst
  • Stage One
  • Stage Two
  • Stage Three
  • Stage Four
  • Certificates and reporting results
  • DCU clearance testing
  • Quality control

You can read and download the full syllabus here.


The assessment is in three parts:

  • Practical assessment - The practical assessment must be carried out by the Tutor during the relevant part of the course for all candidates. This is to ensure that every candidate can demonstrate their ability and correct method for thoroughly reviewing an enclosure (including all four stages of the clearance procedure), locating and taking air samples and the correct use of PPE and RPE.
  • Written examination 1 - This is an open-book examination comprising of approximately 35 (140 marks) short-answer questions. The examination covers the role of the analyst, stage 1 and stage 2 of the clearance process.
  • Written examination 2 - This is an open-book examination comprising of approximately 35 (140 marks) short-answer questions. The examination covers stage 3 and stage 4 of the clearance process, certificates and reporting results, DCU clearance testing and Quality control.

Candidates who pass all the parts within 12 months will be awarded a (P404) Proficiency Certificate in Clearance Testing and the Requirements of a Certificate for Reoccupation.

To take the P404 certificate, a candidate should have:

  • Awareness of the contents of HSG248 Asbestos: The Analysts’ Guide, and in particular Chapter 6: Site clearance and certification.
  • Prior experience of undertaking clearance testing including air sampling, fibre counting and issuing certificates for reoccupation.
  • Previous training to cover the core competences outlined within the foundation material detailed within Table A9.1 of HSG248 Asbestos: The Analysts’ Guide. This may be achieved by in-house learning or through the P400 foundation module.
  • Previously taken the BOHS module P403 – Air Sampling and Fibre Counting (PCM) (P403 and P404 courses with their examinations either run concurrently or as a combined course can be deemed as meeting this requirement).

Contact us by emailing [email protected] to find out more.