Waste piping from aspirators, sterilizers or any other equipment which would produce a partial vacuum by cooling shall discharge to the drainage piping system through an air gap into a waste receptor. The minimum size shall be 1 inch (25 mm) and the maximum length of the indirect waste shall not exceed 15 feet (4.57 m) and shall be provided with cleanouts at every 90 degree turn which are accessibly located. Each indirect waste pipe shall be individually piped to the waste receptor with material that is required by this chapter. Waste receptors serving indirect pipes connected to the above equipment shall be located in the same room. Each waste receptor shall be trapped and vented as required by this chapter. The air gap shall be not less than two times the diameter of the indirect waste pipe.