2.13.2. Timber shores:(1) Rectangular shores shall be at least 89 mm × 89 mm on each side.
(2) Circular shores shall have a minimum diameter of 100 mm.
(3) When shores are spliced end to end, the joint shall be reinforced so as to have the same strength as the shore itself. The joint shall be covered with a piece of the same width as the shore and at least 750 mm in length on 2 adjacent sides of the shore. It is not necessary for the shore parts to be placed end to end when tested assembly clamps are used.
(4) Each part of the spliced shore shall be braced independently in a horizontal manner and, in addition, braced diagonally.
(5) When wedges are used to facilitate the vertical adjustment and removal of shores, they shall be placed on each side of the shore. The vertical space filled by the wedges shall not be greater than the thickness of one wedge.
(6) The timber used for shores shall fulfil the following conditions:(a) it shall be in good condition, shall be derived from species having long non-breaking fibres and shall be free from any defect that might impair its strength;
(b) it shall be of a quality equal to No. 1 spruce;
(c) if it is in the form of logs, it shall be debarked;
(d) it shall not be covered with paint or any opaque coating.