A Commercial Kitchen Hood, like other products such as electrical appliances, can obtain a listing through a third party testing and certification laboratory (laboratory). A hood manufacturer can contract with a laboratory and have their product tested to the prevailing standard. If the manufacture proves that they can meet all of the requirements of the prevailing standard they then can contract with the laboratory to place the laboratories mark on their product. The manufacturer will be subject to quarterly unannounced inspections to insure the listed product is manufactured in accordance with its listing. The manufacturer can continue to display the laboratories mark as long as the manufacturer is in good standing and can prove they are in compliance with their listing to the laboratory.