Occupational Health and Safety Code

The Occupational Health and Safety Code provides specific technical health and safety rules and requirements for Alberta workplaces.

Alberta Regulation 191/2021

Schedule 9 Shoring Component Dimensions

Contents

 

Shoring components used in excavations, trenches, tunnels and underground shafts

[ See subsections 457(1), 457(2) ]

 
  Uprights Stringers Cross‑braces


Soil type


Depth of excavation
(metres)


Minimum dimensions
(millimetres)

Maximum horizontal spacing
(millimetres)


Minimum dimensions
(millimetres)

Maximum vertical spacing
(millimetres)
Minimum dimensions
(millimetres)
Maximum spacing
(millimetres)
Width of trench

Vertical


Horizontal
Less than
1.8 metres
1.8 to
3.7 metres

Hard
and
compact
1.5 to 3.0 38 x 235 1800 89 x 140 1200 89 x 89 140 x 140 1200 1800
More than
3.0 to 4.5
 
38 x 235
 
1200
 
89 x 140
 
1200
 
89 x 140
 
140 x 140
 
1200
 
1800
More than
4.5 to 6.0
 
38 x 235
 
10
 
140 x 140
 
1200
 
140 x 184
 
140 x 184
 
1200

1800
Likely
to crack
or
crumble
1.5 to 3.0 38 x 235 1200 89 x 140 1200 89 x 140 140 x 140 1200 1800
More than
3.0 to 4.5
 
38 x 235
 
900
 
140 x 140
 
1200
 
140 x 140
 
140 x 184
 
1200
  
1800
More than
4.5 to 6.0
 
38 x 235
 
10
 
140 x 184
 
1200
 
140 x 184
 
140 x 184
 
1200
 
1800
Soft,
sandy
or
loose
1.5 to 3.0 38 x 235 10 140 x 140 1200 140 x 140 140 x 184 1200 1800
More than
3.0 to 4.5
 
38 x 235
 
10
 
140 x 184
 
1200
 
140 x 184
 
184 x 184
 
1200
 
1800
More than
4.5 to 6.0
 
38 x 235
 
10
 
184 x 184
 
1200
 
140 x 184
 
184 x 235
 
1200
 
1800