Going from my experience in high care cheese packing business ,
- Picture 1: Possible be not,as the open packs have the bottom of crates above them with no covering leading to potential cross contamination
- Picture 2+3: This wouldnt be ok, cross contamination from floor to cutting belt possible- better to have stainless holder made beside the line to have the trays sit into
- Picture 4: Again cross contamination issues from the trays that may have had floor contact.
In pictures 1 & 4 your crates sit directly on the floor to reduce the risk of cross contamination might be an idea to have holders from them to keep them off the floor, thus keeping them clean.
In general we used to have red/black trays for floor contact and blue for non floor contact. But we tried to have all trays off the floor using custom made holders.This then ensured all waste from the production line wouldn't be classed as floor waste. but could be brought up a class to something we could sell on for thermal processing instead of being floor waste and having to pay someone to take it.
Others may have different opinions though.