Your question is, why is there an emergency exit in the canteen? Not only should the canteen have an emergency exit, but every room in a factory should also have one for the safe escape of occupants in case of fire or other emergencies. Even the factory premises and compound should have emergency exits.
According to your statement, you spend a bit of time in the canteen, and that's why you question the need for an emergency exit. It is important to remember that emergencies can occur at any time, and canteens are often full of fire hazards.
Additionally, you are required to obtain a No Objection Certificate (NOC) from the fire officer for the canteen. The fire officer will also ensure that you have complied with the provisions for emergency exits.
Please let me know if you need any further assistance.