Paragraph 1

For the purposes of regulation five the minimum percentage of incombustible matter in relation to any coal shall be determined by reference to the volatile matter content of that coal calculated on an ash-free dry basis in accordance with the following table—

Volatile matter content of coal (Per cent.)	Minimum percentage of incombustible matter required
Not exceeding
20	50
22	55
25	60
27	65
30	68
32	70
35	72
Exceeding
35	75