At least from my experience in the UK, GMP auditors would not likely require the seamer to be a CCP. I suggest you run risk rating/hazard analysis on each step in your process (impact rating x likelihood) and only enter into your CCP decision tree if the hazard is significant enough. There isn't any set rule about how to define your risk rating or CCP decision tree, but for example ours looks like this:
Impact ratings: 1 = Low (hazard might cause disgust but no significant adverse physical health effect), 3 = Moderate (might cause mild adverse physical health effect with consistent exposure), 5 = Severe (consumption might cause severe physical problems).
Likelihood ratings: 1 = Very Low (it can occur less than once a year), 1.5 = Low (can occur once per month per year), 3 = Moderate (can occur once per week to once per month), 5 = Severe (can occur every batch to once per week).
Score ≤ 3 Define preventatives measures, but do not enter decision tree: no CCP or PRP+. Normal preventative measures will cover hazards.
Score >3 Define preventative measures to prevent, eliminate or reduce hazard to an acceptable level AND enter decision tree.
It's not perfect and it can be awkward to fit every hazard into this rating, but definitely still a useful tool. I would think that the impact rating from improperly sealed cans would be quite low (bad for quality and reputation but little harm to customer).
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Francesco Mayell
Co-Head Brewer
Brixton Brewery
London
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