Time between surveillance audits

Answer:
Surveillance audits have to be performed at least once a year. Consider a certification audit performed in November 2018, the first surveillance audit will take place in November 2019, and the second (and last) surveillance audit in November 2020. After this, in November 2020, the certificate would expire, and a company could go for the recertification audit.

Some certification bodies schedule surveillance audits within a time frame inferior to 12 months to avoid a situation where a surveillance audit find major nonconformities and there is no time to close those nonconformities until the 12 month limit after the last audit, situation that should translate into a loss of certification.

The following material will provide you information about surveillance audits:
- ISO 9001 – What is an ISO 9001 surveillance audit? - https://advisera.com/9001academy/blog/2016/10/18/what-is-an-iso-9001-surveillance-audit/ dit/
- free online training ISO 9001:2015 Lead Auditor Course - https://advisera.com/training/iso-9001-lead-auditor-course/
- book - Discover ISO 9001:2015 Through Practical Examples - https://advisera.com/books/discover-iso-9001-2015-through-practical-examples/