Usually happens within infection control (doing everything in the correct way costs money).
Google manufacturers website and make 100% sure you are correct.
Google HTM-0105 (or whichever is the relevant piece of legislation, if not sure ask your tutor).... Make 100 % sure you are correct.
Approach your infection control lead/manager and draw attention to the oversight... Hopefully they will correct the workplace policy. (Genuine mistakes/oversights can happen to anyone including our bosses so make sure they don't feel like you are picking a fight with them).
If they refuse to rectify or discuss the issue after a week or two, email the registered manager and cc the business owners, every registered clinician and nurse who works there asking everyone for thier ideas on how to fix the problem... It's still a friendly workplace chat at this stage but no-one can pretend to be unaware of the issue.
If no progress after a week or two send a letter registered post to the registered manager (so they cannot pretend they did not receive the letter).
If after a week or two the registered manager refuses to amend the policy then follow the steps for whistle blowing.
how would I deal with workplace procedures conflicting with manufacturers instructions or current legislation?
I am currently doing a course and this is one of the questions I am struggling with.