Inquiry: ISO 17025 accreditation of a microbiological laboratory

ISO 17025 is applicable for all testing and calibration laboratories. There is no mandatory requirement to use standardized methods. When using a in-house developed method you have to show you can meet the performance requirement of the method to fit the purpose. In other words, achieve suitable accuracy and precision and other parameter such a s limit of detection, based on need and risk. i.e. tolerated variation in results.

For accreditation all mandatory requirements of ISO 17025 must be met. For technical requirements this includes method validation, ongoing internal quality control to ensure the validity of your results and participation in a proficiency testing scheme or interlaboratory comparison. I suggest you engage with your quotation body and pose the question to them of how you would proceed for your accreditation in your field. 

The Whitepaper Clause-by-clause explanation of ISO 17025:2017 may assist you, available at https://info.advisera.com/17025academy/free-download/clause-by-clause-explanation-of-iso-17025/

For more information on the mandatory requirements, see the Whitepaper Checklist of mandatory documents required by ISO 17025:2017 at https://info.advisera.com/17025academy/free-download/checklist-of-mandatory-documents-required-by-iso-17025