In an hour, they should start by explaining the job and what you will be expected to do (a) at first (b) after a year or so. Ask any questions so you understand what is expected of you. Also ask how new employees usually take to get up to speed and how they learn anything new. Try to find out what they're looking for in an ideal candidate (so that, later in the interview, you can mention how you have those attributes)
Towards the end, if they think you're a good bet, they should tell you about salary scheme, pension, sports and social club - things that are of no interest if you don't get the job but should attract you to the company.
Then, they will be looking for evidence of whatever you said in your application form/CV; and also to assess your character/are you the sort of person you are. Try to imagine yourself into the job, and answer and behave as an established employee would (but don't try to misrepresent yourself).
"I have much experience of X"
"Tell me about a time when you had to do X"
"What problems do you find when doing X, and how do you overcome them?"
"I am thoroughly trained in Y and am qualified to 16th Edition"
"In 16th Edition, what are the requirements for safe isolation of a high-pressure supply in a commercial kitchen?"
"I have a friendly and co-operative attitude to my colleagues and customers"
"Please work with Chimp here to assemble this Lego into a Christmas tree, while we observe you"
(this one is more common for supervisors/managers)
"What kind of people to you find it difficult to get on with? Give an example. How did you minimise or overcome the problem"
At the end, they should ask if there's anything more you want to ask. Have some Q's ready (write them down and take your notebook with you so you can write down things you don't want to forget). Have a pen in your pocket. Don't ask "how much money can I make? How much paid sickness can I have?" Ask "what training can I get? What's a typical career progression for the first 5 years?"
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