7 Pa. Code § 108.15
(b) Classification criteria. The classifications of the fineness of agricultural liming materials, as set forth in this subsection, are the minimum percentages by weight which shall be able to pass through various sizes of United States Standard sieves to earn a particular classification:
| Classification | Sieve Size Minimums |
| Fine-sized | 95% through a 20 mesh sieve 60% through a 60 mesh sieve 50% through a 100 mesh sieve |
| Medium-sized | 90% through a 20 mesh sieve 50% through a 60 mesh sieve 30% through a 100 mesh sieve |
| Coarse-sized | Agricultural liming materials that fail to meet the minimums for fine-sized or medium-sized classification, as set forth in this subsection. |
The provisions of this § 108.15 adopted March 4, 1994, effective March 5, 1994, 24 Pa.B. 1179.