ATTMA Air Tightness Testing Audit Process

Once accredited and registered as members of the ATTMA Schemes, accreditation shall be maintained through a process of continual surveillance auditing.

These audits will cover aspects of the firms’ operations and testing ability in line with the requirements set out in relevant NOS documents and the MTC.

Firms must have procedures in place to control their activities and demonstrate their competence and compliance with the relevant NOS and the MTC. 

There are three types of auditing that will be carried out on members

Auditing of Quality Management

On-Site Witness Testing

Distance Auditing

Audit Frequency

Quality Management On-site Witness Distance
Year 1
Year 2
Year 3
Year 4
Year 5

As defined in the CoA and subject to a review of the Firm’s performance and audit history on a risk-based approach, the frequency of auditing may be extended to up to three yearly.

Year 3 and 4 – This frequency will be continually reviewed by the Scheme Manager. It may be increased, or an additional audit required, based on factors such as audit outcomes, significant complaints and changes of testers within the business.

Specialist Applications will have an increased audit regime.


All auditors will be approved in advance by the Scheme Manager by undergoing training and/or assessment from a already approved auditor. This is managed by an internal document.

Auditors work to the 6 principles of auditing which require:

1.Integrity – The foundation of professionalism
2.Fair Representation – to give a fair representation of the company
3.Due Professional Care – applying diligence and judgement in auditing
4.Confidentiality – all information shared is secure
5.Independence – the basis for impartiality, providing objective conclusions
6.Evidence Based Approach – giving a rational method for reaching reliable and reproducible audit conclusions