Scaffold planks must be examined prior to erection on a scaffold and at regular intervals during use to ensure that the planks remain in a safe condition.
The wood plank must be No. 1 construction grade lumber, or better, nominal size 50mm by 250mm (2" by 4"). They must be properly seasoned and free from bow, crook, cup or twisted warp.
Planks with splits wider than 10mm (3/8") and lengthwise splits closer than 75mm (3") to the edge of the plank must be removed from service. When a lengthwise split in a plank exceeds 1/2 the length of the plank, then that plank should also be removed from service.
NOTE: Plywood cleats should not be used along the length of the plank to keep planks from splitting. It has been found that the cleats may cause the plank to rot beneath where the cleat has been fastened, due to moisture accumulation and retention. Scaffold planks with cleats should be inspected immediately and removed from service if there is any indication of wood rot.
Proper end cleats must still be used to prevent the plank from sliding off the scaffold frame.
Pre-manufactured metal or laminated scaffold planks are a good alternative to standard wood planking, since they are of a consistent quality and provide a long service life.
The grain is not to exceed a slope of 1 in 12 along the length of the plank.
Knots must be sound, tight, and spaced well apart. Maximum knot size for a 50mm by 250 mm plank is 50mm (2"). Knots on the edge of a plank must not be greater than 10mm(3/8") width, or spiked across the entire width.