There are hundreds of health codes that vary throughout the US but in most cases all codes will require at least the following: 3 compartment sink, Hand wash sink, fresh and grey water tanks (grey water is normally 15% larger than the fresh water tank), hot water, & smooth cleanable surfaces. Cooking operations will require a commercial hood ventilation system with a stainless steel backsplash and a manual fire extinguisher.
Remember, even if your local health inspector tells you that you are not required to have a fire suppression system check with the fire marshal, he has a higher jurisdiction than your health inspector. Another thing to think about, if you choose not to have this system installed and travel out of your local area or into another state where it is required and mandatory, you will not be permitted to open and will lose any fees paid to that event. But, if you are trying to keep the initial start up cost down, it is something that can be added at a later time. Whew, that was a mouth full.
Keep in mind though that concession trailers are notoriously hard on generators and if your generator needs to be repaired in the future your trailer is grounded as well. The other option is to buy a generator locally and throw it in the back of your pick up in case of emergency. (pay for the extended warranty) That way if you ever have a problem, you can take it back to your local store and get another one and you back in business.
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