Canadian federal meat plants require ALL employees to have training with a quiz at the end as proof of understanding. Yes it's a massive job, but the company will benefit from it in the end. It can also be used for disciplining employees........they can no longer say "i didn't kow...." when you can pull out a quiz that says otherwise
Breakdown employees by shift, and area of production and length of service, then start scheduling them in for basic HACCP and GMP training, keeping it small, not more than 20 souls per session. There should be a simple 1 page, printed on both sides quiz that is suitable for the department or process....some general GMP questions and then specific for the job function........maintenance could have ques tons about ensuring the tools are kept sanitary for example
On the floor employees can be verified against a short on the job interview and observations. CCP monitoring employees should have separate training and separate verification
The amount of training given with quizzes will depend on your productions risks and finished goods