# Mines (Working Facilities and Support) Act 1923, Paragraph 1


The area shall extend laterally on each side of (but not including) the inner area of protection to the following distance therefrom :—
If the depth of the seam is 160 yards or under
Nil.
If the depth of the seam exceeds 160 yards, but does not exceed 170 yards
1½ yards.
If the depth of the seam exceeds 170 yards, but does not exceed 180 yards
2½ yards.
If the depth of the seam exceeds 180 yards, but does not exceed 190 yards
4½ yards.
If the depth of the seam exceeds 190 yards, but does not exceed 200 yards
5½ yards.
If the depth of the seam exceeds 200 yards, but does not exceed 210 yards
7 yards.
If the depth of the seam exceeds 210 yards, but does not exceed 220 yards
8 yards.
If the depth of the seam exceeds 220 yards, but does not exceed 230 yards
9 yards.
If the depth of the seam exceeds 230 yards, but does not exceed 240 yards
9½ yards.
If the depth of the seam exceeds 240 yards, but does not exceed 250 yards
10 yards.
If the depth of the seam exceeds 250 yards
To a line descending outwards from the railway or works at an angle of one horizontal to five vertical from a point on the boundary of the railway or works at rail level until the depth of 650 yards is reached and thence descending vertically.

---
Source: https://www.legislation.gov.uk/ukpga/Geo5/13-14/20/schedule/SECOND/paragraph/1 (the official version)
Page: https://openlegislation.uk/mines-working-facilities-and-support-act-1923/schedule-SECOND/paragraph-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.