This test is used to evaluate the strength of a backrest due to vertical forces applied to the sample. The test applies to backrests that are fixed or can be fixed as to retrain pivoting and have a backrest height less than 38 inches measured from the floor. The sample will be secured without inhibiting movement of the back or arms. A 16 inch loading device will be positioned vertically to the backrest of each seating position of the sample. All seating positions will be tested simultaneously. A load with a vertical force of 200 lb. will be applied to each seating position for one minute and then a load of 300 lb. will be applied for one minute in the same fashion.