Health Inspector qualification

ISO 14001:2015 has no particular requirements concerning those that will implement an environmental management system or be responsible for its operation, maintenance and improvement.
Each organization is free to define competence requirements for that role.
Being a Health Inspector may give you some experience with regulations and with the task of working with others to follow rules. Besides that qualification I recommend learning about ISO 14001:2015 requirements, learning about good internal audit practices, and learning about good implementation practices.
 
The following material will provide you more information about training:
Free webinar - Free webinar - How to use a Documentation Toolkit for the implementation of ISO 14001 - https://advisera.com/14001academy/webinar/how-to-use-a-documentation-toolkit-for-the-implementation-of-iso-14001-free-webinar-on-demand/
Enroll for free in this course – ISO 14001:2015 Foundations Course - https://advisera.com/training/iso-14001-internal-auditor-course/
Enroll for free in this course - ISO 14001:2015 Lead Implementer Course - https://advisera.com/training/iso-14001-lead-implementer-course/
Enroll for free in this course - ISO 14001:2015 Internal Auditor Course - https://advisera.com/training/iso-14001-internal-auditor-course/
Book – The ISO 14001:2015 Companion - https://advisera.com/books/the-iso-14001-2015-companion/