Each area can have slightly different building codes depending on the location of the building. Federal, state, and even local building codes can have an impact on determining the door closer required. The Builders Hardware Manufacturers Association (BHMA) and American National Standards Institute (ANSI) provide extensive standards for door closers. The full list can be found here. Generally, each door closer needs to meet different levels of performance broken up in 3 grades with 1 being the highest and 3 being the basic level. Performance is judged based on cycle testing as well as closing force and finish tests. The tests are done in a neutral air pressure laboratory at 60-85 degrees F.