34 Pa. Code § 45.41 – Circular mill.

(a) Double circular mill. This type of mill shall be as follows:
1. (1) The upper saw of each double circular mill shall be provided with a hood or guard.
2. (2) On all double circular mills, the horizontal distance from the side of the saw to the nearest post of the husk or frame shall be at least 1 inch greater than the clear vertical distance between the collars of the top and bottom saws.
3. (3) Either a screen of wire cloth, or other suitable device, shall be installed on double circular saw mills to protect the sawyer from flying particles, or the sawyer shall be provided with a fine mesh wire face mask.
(b) Single circular saw. The saw of each single circular mill shall be provided with a hood or guard, if the logs are cut with the bottom half of the saw.
(c) Safety guides. All circular saw mills shall be equipped with safety guides which may be adjusted without the use of a wrench or other handtool.
(d) Spreader. All circular saw mills shall be equipped with an effective spreader (splitter). In the case of circular sawmills used for edging lumber, this spreader (splitter) shall be solid and stationary and shall extend at least 20 inches above the head blocks.
(e) Speed limit. Brackets or edging supports shall be provided between the saw and the side of the husk.
(f) Rock saw. The peripheral speed of circular head saws shall not exceed 10,000 feet per minute.
(g) Saw cracks. No circular mill saw shall be used when it is found to have developed a crack, the depth of which exceeds that indicated in the following table:
Maximum Depth of Crack
(in inches) Saw Diameter
(in inches)
.5 12
1 24
1.5 36
2 48
2.5 60

Maximum Depth of Crack (in inches)	Saw Diameter (in inches)
.5	12
1	24
1.5	36
2	48
2.5	60