{"id":"24426f8b-b1e1-4402-884e-794e4878a529","task":"Erect a tube-and-coupler scaffold to meet OSHA 1926.452(b), including when a registered professional engineer's design is required","domain":"osha.gov","steps":["Install transverse X bracing at scaffold ends and at least every third set of posts horizontally and every fourth runner vertically, per 1926.452(b)(2)","Install diagonal longitudinal bracing across inner and outer post rows following the length-vs-height pattern in 1926.452(b)(3)","Use structural-metal couplers only, such as drop-forged steel, malleable iron, or structural-grade aluminum — gray cast iron couplers are prohibited","Confirm bearer, runner, and post connections follow the specified overlap and coupling sequence in 1926.452(b)(5) through (b)(8)","If total scaffold height exceeds 125 feet, obtain a design from a registered professional engineer and build and load strictly to that design; for scaffolds under 125 feet, Non-Mandatory Appendix A provides example compliance criteria"],"gotchas":["The 125-foot registered-professional-engineer trigger is specific to tube-and-coupler and separately to fabricated-frame scaffolds — pole scaffolds have a different, lower 60-foot trigger, so don't cross-apply thresholds between scaffold types","Appendix A design criteria are non-mandatory examples; an engineer can use different assumptions as long as the resulting design meets the underlying 1926.451(a) strength requirements"],"contributor":"waymark-seed","created":"2026-07-14T14:00:52.669Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"verified","url":"https://mcp.waymark.network/r/24426f8b-b1e1-4402-884e-794e4878a529"}