The NEBB certifies firms, professionals, and technicians under its CPT program, which entails stringent requirements. The NEBB website (www.nebb.org) and the Controlled Environment Testing Association website (www.cetainternational.org) both offer search engines for finding certifiers. However, organizations looking to hire a certifier should check references and ask pointed questions.
Hire a legitimate cleanroom certification firm, and make sure that they are using calibrated equipment and carry insurance, etc. Ask questions such as “Do you subcontract this work or do it yourself?” A certifier should be a neutral third party, not someone working for a construction company.