You won't find the answer to your specific question in the SQF manual. However, you will find that protecting product, materials, etc is mandatory of course. I would suggest you run a risk analysis taking in the surroundings (not just what is above) like is the conveyor low on level with people walking, air factors, etc and of course where the conveyor goes (washer.)
It should not be an issue, back you need the backup documentation as "verbal don't go."
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