After reviewing the general requirements for scaffolds, refer to the regulations listed below (and any other applicable Safety Orders (SOs) for the specific type(s) of scaffold in use to determine whether these requirements replace or augment the general requirements.
The requirements listed below are unique to each specific type of scaffold listed:
-Tubular welded scaffold systems 1644
These scaffold systems are commercially fabricated and must meet the following requirements:
a. Frames must nest with coupling or stacking pins to provide proper vertical alignment.
b. Frame panels must be vertically pinned if uplift may occur.
-Tower and rolling scaffolds
The specifications for tower and rolling scaffolds are as follows:
a. The “height-to-base” must not exceed 3:1 unless the scaffold is secured.
b. A screw jack must extend 1/3 of its length into the leg tube and the exposed thread must not exceed 12 inches.
c. Two wheels or casters must swivel; all four must lock.
d. A fully planked platform is required.
e. All frame and center joints shall be locked together by lock pins, bolts, or equivalent fastenings.
f. The scaffold must have horizontal diagonal bracing (go to the 'docs' tab above to see Illustration 9).
g. Railings are required if the platform is 7 1/2 feet or more above grade.
h. Ladders or other unstable objects shall not be placed on top of rolling scaffolds to gain greater height.
i. When scaffolds are built on motor trucks or vehicles, they must be rigidly attached to the truck or vehicle.
j. Trucks or vehicles that have scaffolds attached to them shall have a device in use whenever employees are on the scaffold that prevents swaying or listing of the platforms.
k. Employees may ride on rolling scaffold moved by others below if the following conditions exist:
1. The floor or surface is within 3 degrees of level, and free from pits, holes, or obstructions.
2. The minimum dimension of the scaffold base, when ready for rolling, is at least 1/2 of the height. Outriggers, if used, shall be installed on both sides of staging.
3. The wheels are equipped with rubber or similar resilient tires. For towers 50 feet or over, metal wheels may be used.
4. The manual force used to move the scaffold shall be applied as close to the base as practicable, but not more than 5 feet (1.5 meters) above the supporting surface of the scaffold.
5. Before a scaffold is moved, each employee on the scaffold shall be made aware of the move.
6. No employee shall be on any part of the scaffold which extends outward beyond the wheels, casters, or other supports.
l. Employees may ride and move on a Self-Propelled rolling scaffold while on the platform without assistance from others below provided the following conditions are met:
1. All of the provisions in 1646(i) shall be met, except that the scaffold need not be moved by others below.
2. The scaffold platform shall not be more than 4 feet above the floor level.
3. The working platform shall be no less than 20 inches in width with a maximum 1 inch space between platform planks.
4. Wheels or casters of rolling scaffolds shall be provided with an effective locking device that is used in accordance with 1646(c) or rolling scaffolds shall be provided with an effective device that is used to prevent movement of the scaffold when workers are climbing or working on the scaffold.
5. The use of power systems such as motor vehicles, add-on motors, or battery powered equipment to propel a rolling scaffold is prohibited.
m. Employees who ride on rolling scaffolds and employees that assist in moving employees riding on a rolling scaffold shall be trained on the hazards associated with riding on a rolling scaffold as per 1646 and 1509.
a. General requirements for suspended scaffolds (swing staging).
Most suspended scaffolding has a two-point suspension supported by hangers or stirrups. The following applies:
1. Each wire is suspended from a separate outrigger beam or thrustout.
2. Multi-stage units or units with overhead protection must be equipped with additional suspension lines to support the scaffolding in case the primary suspension system fails.
3. The scaffold must be inspected daily by a qualified person and tested frequently.
4. When a suspended scaffold is left unattended in an elevated position, it shall be securely lashed to the building and be cleared of all tools, buckets, or other moveable materials.
5. All hoisting mechanisms and metal platforms must meet nationally recognized standards.
6. Outrigger beams must be secured in a saddle and anchored at one end to solid structure. The inboard end must be tied back.
7. The beam must be capable of supporting four times the intended load.
8. Use of a ladder as a platform is prohibited even if a horizontal work surface is added over the rungs.
9. The load limit is one person per suspension rope.
10. An insulated wire suspension rope is required when workers are welding, burning, sandblasting, or using any chemical substance which may damage the rope.
11. A separate safety harness and lifeline are required for each worker.
12. Platform dimensions must be as follows:
• Width = 14 inches to 36 inches = 24 inches to 36 inches if the platform is used by cement masons.
• Span = 10 feet (2" x 10" planks). 1660(e); = 12 feet (2" x 12" planks).
• Bolster (ledger) = 2" x 4" cross section.
b. Specific requirements for suspended scaffolds:
1. Powered suspended scaffolds 1667
The general rules for swing scaffolds apply except as listed below:
• The minimum platform width must be 20 inches.
• Railings are required on open sides and ends and on all sides if the scaffold is suspended by one rope.
• The load limit is 425 lbs. for a ladder-type platform.
• Controls must be of the dead-man type.
• Load release units for fast descent are prohibited.
2. Interior hung suspended scaffolds
These scaffolds are of a wood or steel-tube-and-coupler type, and they are suspended from a ceiling or roof structure. The general and suspended scaffold rules apply.
• Suspension ropes must be wrapped twice around supporting members and ledgers.
• Ends of wire rope must be secured with at least three clips.
3. Float suspended scaffolds.
These scaffolds are intended for such work as welding, riveting, and bolting.
• Platform size: 3 feet x 6 feet. x 3/4 inches plywood.
• Rope: 1 inch diameter manila (min.).
• Load limit: Three people.
• Personal fall protection and a separate lifeline: required for each person.
4. Boatswain’s chair.
The use of a boatswain’s chair requires training or experience.
• Platform size: 10 inches x 24 inches x 2 inches.
• Rope: 5/8 inch diameter manila (min.) and 3/8 inch diameter protected wire for welding.
• Personal fall protection and a separate lifeline: required 1662(c)
• Area below: barricaded.
5. Needle-beam scaffolds.
The specifications for needle-beam scaffolds are
• Beam size: 4 inches x 6 inches x 10 feet.
• Rope: 1 1/4 inch diameter manila.
• Personal fall protection: Required in accordance with Article 24 in the Construction Safety Orders (CSOs).
Note: go to the 'docs' above, Illustration 10, to see the hitches for holding needle beams in.
6. Outrigger scaffolds.
Outrigger scaffolds are regulated as follows:
• Brackets or beams must be anchored or braced against turning, twisting, or tipping.
• Platform: at least two 2 inches x 10 inches planks.
• Beam size: 3 inches x 12 inches (min.).
• Beam length: Outboard of fulcrum must not exceed 6 feet; inboard must be 1 1/2 times the outboard section.
Note: for multi-level structures the units must be designed by a California registered Civil Engineer.
7. Bracket scaffolds (light trades).
Brackets must be bolted through walls, welded to tanks, properly secured to metal studs, or hooked over a supporting member.
• Platform: 20 inches x 10 feet (min.)
• Load limit: Carpenter’s type = two workers and 75 lbs. of equipment.
8. Horse scaffolds.
The specifications for horse scaffolds are as follows:
• Platform width:
i. Light trades = 20 inches (min.); 10 inches if the platform is less than 4 feet high.
ii. Heavy trades = 4 feet (min.).
iii. Width of base legs = 1/2 x height (min.).
i. Collapsible horse = 6 feet (max.).
ii. Single horse = 10 feet (max.).
iii. Two tiers (max.) = 10 feet (max.).
9. Ladder jack scaffolds.
The specifications for ladder jack scaffold platforms are as follows:
• Span = 16 feet (max.).
• Height = 16 feet (max.).
• Width = 14 inches (min.)
• Load = two workers (max.).
Note: ladders must be Type I, IA, or IAA duty rated ladders in accordance with 3276(c). Job-built ladders shall not be used for this purpose. Also, a safety line is required for each worker.
10. Window jack scaffolds.
The specifications for window jack scaffolds are as follows:
• Only one window per scaffold is permitted.
• The load limit is one person per scaffold.
• Fall protection or railings are required.