PDFWAC 296-874-40004
Prevent supported scaffolds from tipping.
(1) You must make sure supported scaffolds with a height to least base dimension ratio of greater than four to one are prevented from tipping by one or more of the following:
(a) Guying;
(b) Tying;
(c) Bracing;
(d) Other equivalent means.
Note: | The least base dimension includes outriggers, if used. |
(2) You must install guys, ties, and braces where horizontal members support both the inner and outer legs of the scaffold.
(3) You must install guys, ties, and braces:
(a) According to the scaffold manufacturer's recommendations; or
(b) At all points where the following horizontal and vertical planes meet:
(i) First vertical level at a height equal to four times the least base dimension.
(ii) Subsequent vertical levels every:
(A) Twenty feet (6.1 m) or less for scaffolds having a width of three feet (0.91 m) or less;
(B) Twenty six feet (7.9 m) or less for scaffolds more than three feet (0.91 m) wide.
(iii) Horizontally at:
(A) Each end of the scaffold; and
(B) Intervals of thirty feet (9.1 m) or less.
Note: | The thirty-foot horizontal intervals are measured from one end of the scaffold to the other. |
(4) You must make sure the highest level of guys, ties, or braces is no further from the top of the scaffold than a distance equal to four times the least base dimension.
(5) You must make sure scaffolds that have an eccentric load applied or transmitted to them, such as a cantilevered work platform, are prevented from tipping by one or more of the following:
(a) Guying;
(b) Tying;
(c) Bracing;
(d) Outriggers;
(e) Other equivalent means.
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050. WSR 15-23-086, § 296-874-40004, filed 11/17/15, effective 12/18/15. Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. WSR 07-17-026, § 296-874-40004, filed 8/7/07, effective 10/6/07; WSR 07-03-163, § 296-874-40004, filed 1/24/07, effective 4/1/07; WSR 05-01-054, § 296-874-40004, filed 12/7/04, effective 3/1/05.]