(1) You must make sure tube and coupler scaffolds over one hundred twenty-five feet high are:
(a) Designed by a registered professional engineer; and
(b) Constructed and loaded as specified in the design.
(2) You must leave existing platforms undisturbed until new bearers have been set in place and braced before moving the platforms to the new level.
(3) You must install crossbracing across the width of the scaffold that meets all of the following:
(a) Bracing is installed at:
(i) Each end of the scaffold; and
(ii) At least at every third set of posts horizontally and every fourth runner vertically.
(b) Bracing extends diagonally from the:
(i) Outer posts or runners upwards to the next inner posts or runners; and
(ii) Inner posts or runners upwards to the next outer posts or runners.
(4) You must install building ties:
(a) At the bearer levels between the crossbracing; and
(5) You must install longitudinal bracing on straight run scaffolds as follows:
(a) Diagonally in both directions across the inner and outer rows of posts;
(b) From the base of the end posts upward to the top of the scaffold at approximately a forty-five degree angle;
(c) As close as possible to the intersection of the bearer and post or runner and post;
(d) If the scaffold is longer than it is tall, repeat the bracing beginning at every fifth post;
(e) If the scaffold is taller than its length, install the bracing:
(i) From the base of the end posts upward to the opposite end posts; and
(ii) In alternating directions until reaching the top of the scaffold.
(6) You must attach bracing to the runners as close to the post as possible, if bracing can't be attached to the post.
(7) You must make sure bearers meet all of the following:
(a) Are installed transversely between posts;
(b) If the bearer is coupled to the post, have the inboard coupler bear directly on the runner coupler;
(c) If the bearer is coupled to the runners, have the couplers as close to the posts as possible;
(d) Extend bearers beyond the posts and runners;
(e) Provide full contact with the coupler;
(f) The bottom bearers are located as close to the base as possible.
(8) You must make sure runners meet all of the following:
(a) Are installed along the length of the scaffold;
(b) Are located on both the inside and outside posts at the same height;
(c) Are interlocked on straight runs to form continuous lengths and are coupled to each post;
(d) The bottom runners are located as close to the base as possible.
Note: | Tube and coupler guardrails and midrails installed on outside posts can be used in lieu of outside runners. |
(9) You must make sure couplers are made of a structural metal, such as drop-forged steel, malleable iron, or structural grade aluminum.
(10) You must prohibit using couplers made of gray cast iron.