7 Pa. Code § 59a.330
If surge tanks are used for hot milk and temperatures of products including foam being held in the surge tank during processing is not maintained at a minimum of 150° F, two or more surge tanks shall be installed with cross connections to permit flushing and cleaning during operation. Covers easily removable for cleaning shall be provided and used at all times.
This section cited in 7 Pa. Code § 59a.326 (relating to equipment and utensils).