A person may not permit fugitive particulate matter to be emitted into the outdoor atmosphere from a source specified in § 123.1(a)(1)-(9) (relating to prohibition of certain fugitive emissions) if the emissions are visible at the point the emissions pass outside the person's property.
25 Pa. Code § 123.2
This section cited in 25 Pa. Code § 77.108 (relating to permit for small noncoal operations); 25 Pa. Code § 123.1 (relating to prohibition of certain fugitive emissions); and 25 Pa. Code §264.521 (relating to design and operating standards).