The scope of this standard covers a method of test for the humidification rate of central-system residential humidifiers intended for use with forced warm air heating and/or cooling systems. This method of test describes the test apparatus@ conduct of the test@ and information to be recorded. Tests covered include methods for measuring electrical power input@ water flow rate@ water temperature@ and water pressure to the test humidifier. Also included are airflow rate@ static pressure@ temperature@ and relative humidity entering and maintained by the test apparatus. Information resulting from the application of this method of test is intended for use by manufacturers@ specifiers@ installers@ and users of central-system residential humidifiers. This method of test does not apply to self-contained humidifiers@ portable humidifiers@ or humidifiers for commercial and industrial applications. PURPOSE This standard establishes a uniform method of laboratory testing for rating central-system residential humidifiers.