Safety requirements for scaffolding in Standards - 29 CFR 7
To be continued:
1910.28(b)(16)
All wood pole scaffolds 60 feet or less in height shall be constructed and erected in accordance with tables D-7 through D-12 of this section. If they are over 60 feet in height they shall be designed by a registered professional engineer and constructed and erected in accordance with such design. A copy of the typical drawings and specifications shall be made available to the employer and for inspection purposes.
1910.28(b)(17)
Wood-pole scaffolds shall not be erected beyond the reach of effective firefighting apparatus.
TABLE D-7 - MINIMUM NOMINAL SIZE AND MAXIMUM SPACING OF MEMBERS OF
SINGLE POLE SCAFFOLDS - LIGHT DUTY
____________________________________________________________________
|
| Maximum height of scaffold
|__________________________________
| |
| 20 feet | 60 feet
______________|________|_____________
| |
Uniformly distributed load.......| Not to exceed 25 |
| pounds per |
| square foot. |
Poles or uprights................| 2 by 4 in........| 4 by 4 in.
Pole spacing (longitudinal)......| 6 ft. 0 in.......| 10 ft. 0 in.
Maximum width of scaffold........| 5 ft. 0 in.......| 5 ft. 0 in.
Bearers or putlogs to 3 ft. 0 in.| |
width..........................| 2 by 4 in........| 2 by 4 in.
Bearers or putlogs to 5 ft. 0 in.| |
width..........................| 2 by 6 in. or 3 | 2 by 6 in. or
| by 4 in. | 3 by 4 in.
| | (rough).
Ledgers..........................| 1 by 4 in........| 1 1/4 by 9 in.
Planking.........................| 1 1/4 by 9 in. |
| (rough)........| 2 by 9 in.
Vertical spacing of horizontal | |
members........................| 7 ft. 0 in.......| 7 ft. 0 in.
Bracing, horizontal and diagonal.| 1 by 4 in........| 1 by 4 in.
Tie-ins..........................| 1 by 4 in........| 1 by 4 in.
Toeboards........................| 4 in. high | 4 in. high
| (minimum)......| (minimum)
Guardrail........................| 2 by 4 in........| 2 by 4 in.
___________________________|__________________|_______________
All members except planking are used on edge.