9% of construction deaths are scaffold-related Scaffold falls injure 29,000 workers every year. 47% of all scaffold catastrophes and deaths are caused by defective scaffolds. Any missing or defective part makes a scaffold less safe. The danger of falling is most common. Scaffold Hazards Ladders and Scaffolds
1926.450 Subpart L - Scaffolds 1926.450: Scope, application and definitions 1926.451: General requirements –Covers the basic variables 1926.452: Specific requirements –For each type of scaffold 1926.453: Aerial lifts 1926.454: Training –Anyone who works from a scaffold or who erects scaffolds must have training. Ladders and Scaffolds 15 X & L
Supported scaffolds must have these features: How Do We Know a Scaffold Is Safe?
1926.450 definitions applicable to subpart Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are hazardous or dangerous to employees, and who has the authorization to take prompt corrective measures to eliminate them.(CPL 2-1.23)
.451 General Requirements For All Scaffolds (a) Capacity –Support its own weight and 4 X the Maximum Intended Load (MIL). –Designed by a Qualified Person and built and loaded to design. –Some Criteria listed in Appendix 'A' Ladders and Scaffolds 17 SUBPARTS X & L
(b) Platform Construction Platforms fully planked or decked Maximum 1” gaps Maximum openings of 9½” if necessary Platforms and walkways minimum 18” wide Guardrails and/or Personal Fall Arrest System (PFAS) for < 18” wide Planks laid at angles other than 90º laid first under planks laid over supports at 90 º Ladders and Scaffolds 20 SUBPARTS X & L
Fully planked with scaffold-grade wood or metal. What Makes a Safe Platform? Ladders and Scaffolds 21 SUBPARTS X & L
Scaffold Platform Construction Front of scaffold no more than 14 inches from face of work For outrigger scaffolds 3 inches Unless secured platforms extend minimum of six inches over support 6"
(b)(3) 14” MAX 18” OR MUST HAVE GUARDRAIL OR FALL PROTECTION
Platform Construction Don’t paint wood, except ID on edges Fully planked between front upright & guardrails Don’t mix scaffold components used unless compatible & strength is maintained [Competent Person decision] Don’t modify mixed scaffold components to make them fit [C.P. decision] No components of dissimilar metals without Competent Person approval Ladders and Scaffolds 27 SUBPARTS X & L Inspect, Inspect, Inspect
This 6-tier scaffold is is anchored to the building with rope through windows. A solid strut anchor is better, especially if not dependent upon friction attachments at both ends. Ladders and Scaffolds 30 X & L SUBPARTS Tie-Ins to the Building
1926.451 (c) Supported Scaffolds Guys, ties or braces required at the 4:1height ratio Repeated every 20 feet for scaffolds three feet wide or less Every 26 feet wider than three feet Installed at each end of the scaffold Horizontal spacing not to exceed 30 feet
You can visually check scaffold alignment. Plumb: Vertical members stand perpendicular to horizon. Level: Horizontal members are parallel to horizon. Square: Horizontal and vertical members form right angles where they connect. Plumb, Level, Square Ladders and Scaffolds 34 X & L SUBPARTS
Ladders and Scaffolds 35 SUBPARTS X & L Foundation and Load Distribution?
Bracing required to prevent tipping for all eccentric applied loads Scaffolds must bear on base plates and mud sills or other firm foundation Footings rigid with no settling or displacement Supported Scaffolds
1926.451 General Requirements (c) Criteria for supported scaffolds (2) Base plates mud sills Mud sills Base plate
Unstable objects shall not be used to support scaffolds or platform units. Unstable objects shall not be used as working platforms. 1926.451 (c) Supported Scaffolds
Poles, legs, posts, frames, and uprights plumb and braced 1926.451 (c) Supported Scaffolds
Distribute loads evenly. Point load over uprights. Evenly distributed – A good practice! Point Loading - When necessary, it should be done over uprights. An unsafe practice! What’s the Best Way to Load the Scaffold? Ladders and Scaffolds 37 SUBPARTS X & L
1926.451 (e) Access Scaffold more than two feet above or below a point of access ladders, stairs, ramps or other similar access provided No cross braces for access! Hook on ladders positioned so as not to tip the scaffold Bottom rung within 24 inches of supporting level Over 35 feet, rest levels every 35 feet
Hook-on ladders compatible with scaffold used Minimum rung width of 11 1/2 inches Rungs uniformly spaced 16 3/4 inches maximum rung spacing Slip resistant treads on stairs and landings 1926.451 (e) Access
Prefabricated scaffold access: –specifically designed and constructed for use as ladder rungs; –Have a rung length of at least 8 inches –Uniformly spaced –Max. spacing 16 3/4 inches ** fixed ladders must have fall protection if length of climb is 24’ or greater.** ** landing ‘rest’ platforms required on fixed ladders at maximum intervals of 50’** 1926.451 (e) Access
No loading in excess of intended or rated load Lean-to scaffolds prohibited CP to inspect for defects each shift Damaged scaffold repaired, replaced or braced Use
USE No makeshift devices to increase height – The 'Drywall Bucket Rule' No ladder to increase height except on 'large area' and: – Side thrust countered, platform secured – Ladder legs on same platform & secured Platforms not to deflect > 1/60 of span Ladders and Scaffolds X & L SUBPARTS 47
No moving of scaffolds with employees on them unless designed by PE for such Must decend mobile scaffolds prior to moving, and lock casters when in position. Safe distance from electric lines: –Insulated lines: Less than 300 volts = 3 feet 300 volts to 50 kilovolts = 10 feet Over 50 kilovolts = 10 feet plus.4 inches for each additional kV; or twice the length of the line insulator but never less than 10 feet Use
Scaffolds erected, moved, dismantled, or altered only under the supervision and direction of a competent person qualified in scaffolds Access scaffolds with snow/ice only to remove Swinging loads near scaffolds must use tag lines Use
Debris shall not be allowed to accumulate on platforms.
Your employer must train you..454 Training Requirements Ladders and Scaffolds X & L SUBPARTS 73
Required at 10 foot height PFAS instead of guardrails on some Fall protection required when scaffold is greater than 14” away from work surface PFAS for erectors/dismantlers where feasible Toprails height = 38” to 45” Crossbracing ‘X’ as top or midrail depending on height Fall Protection Ladders and Scaffolds X & L SUBPARTS 48
Guardrails prevent work falls. ─ Ideal height is 38 inches above work platform. ─ OSHA requires fall protection on platforms 10 feet or higher. Top rail must withstand a force of 200 pounds (or 100 pounds on suspension scaffolds). Only 33% of the scaffolds involved in accidents had guardrails. Guardrails Ladders and Scaffolds X & L SUBPARTS 49
1926.451 (g) Fall Protection Guardrail systems shall be installed along all open sides and ends of platforms. Guardrail systems installed before scaffold is released for use by employees other than erection/dismantling crews.
(h) Falling Object Protection Hardhats required Protect employees below Barricades to exclude working below Toe boards at edges of platforms Allows panels and screens Canopies allowed Ladders and Scaffolds X & L SUBPARTS 53
Using extra planks on edge: – Wire in place – Maintain max. gap of ¼" – Wire or nail ends in place Job-made w/1"x 6" lumber: – Wire/nail/cleat in place – Lighter, easier to handle Ladders and Scaffolds X & L SUBPARTS 54 Toeboard Options
Scaffolds shall remain a minimum of 10 feet away from energized power lines. All power tools and equipment shall be plugged into a GFCI Temporary lighting shall not be connected to the scaffold system by metal components Ladders and Scaffolds X & L SUBPARTS 54 Electrical Hazards
Mobile Scaffolds 3 Plumb; Level square; Braces secured Cross, horizontal & diagonal braces to prevent racking or collapse Mobile scaffolds must comply with other frame requirements Castors - positive lock on wheel and/or swivel Ladders and Scaffolds X & L SUBPARTS 58
Ladders and Scaffolds SUBPARTS 59 Horizontal and diagonal bracing required to prevent “racking”. Most manufacturers provide with fixed length. Mobile Scaffolds 2 X & L
Bricklaying crew working on the upper floor of a three-story building built a six-foot platform spanning a gap between two scaffolds. The platform was correctly constructed of two 2”X12” planks with standard guardrails; however, one of the planks was not scaffold grade lumber and also had extensive dry rot in the center. when a bricklayer stepped on the plank it disintegrated and he fell 30 feet to his death. Fatal fact
Two employees were installing aluminum siding on a farm house when it became necessary to remove a 36-foot high metal pole CB antenna. One employee stood on a metal pick board between two ladders and unfastened the antenna at the top of the house. The other employee who was standing on the ground, took the antenna to lay it down in the yard. The antenna made electrical contact with a 7200-volt power transmission line 30 feet 10 inches from the house and 23 feet 9 inches above the ground. The employee handling the antenna received a fatal shock and the other employee a minor shock. Fatal fact
Don’t allow tools, materials, or debris to collect on scaffold. Never, never throw or drop tools, materials, or equipment. Make sure connections are in place and completely tight. Do not stand on ties. Do not stand on guardrails or plank extensions. Do not overreach outside of the guardrails. Protect Yourself With Good Practice Ladders and Scaffolds SUBPARTS 71 X & L