Construction Safety Requirements




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Saws, Portable Circular


Portable, power-driven circular saws must be equipped with guards above and below the base plate or shoe. The lower guard must cover the saw to the depth of the teeth, except for the minimum arc required to allow proper retraction and contact with the work, and must automatically return to the covering position when the blade is removed from the work.

Saws, Radial


Radial saws must have an upper guard that completely encloses the upper half of the saw blade. The sides of the lower exposed portion of the blade must be guarded by a device that will automatically adjust to the thickness of and remain in contact with the material being cut.
Radial saws used for ripping must have non-kickback fingers or dogs. Radial saws must be installed so that the cutting head will return to the starting position when released by the operator.
Saws, Swing or Sliding Cut-Off
All swing or sliding cut-off saws must be provided with a hood that will completely en-close the upper half of the saw. Limit stops must be provided to prevent swing or sliding type cut-off saws from extending beyond the front or back edges of the table.
Each swing or sliding cut-off saw must be provided with an effective device to return the saw automatically to the back of the table when released at any point of its travel. Inverted sawing of sliding cut-off saws must be provided with a hood that will cover the part of the saw that protrudes above the top of the table or material being cut.

Saws, Table


Circular table saws must have a hood over the portion of the saw above the table, so mounted that the hood will automatically adjust itself to the thickness of and remain in contact with the material being cut. Circular table saws must have a spreader aligned with the blade, spaced no more than 1/2 inch behind the largest blade mounted in the saw. This provision does not apply when grooving, dadoing, or rabbiting.
Circular table saws used for ripping must have non-kickback fingers or dogs. Feeder attachments must have the feed rolls or other moving parts covered or guarded so as to protect the operator from hazardous points.

Scaffolds


General Requirements

Scaffold means any temporary elevated plat-form (supported or suspended) and its supporting structure (including points of anchorage) used for supporting employees or materials or both.


Fall protection—such as guardrail and personal fall arrest systems—must be provided for each employee working on a scaffold more than 10 feet above a lower level.
Employers must have a competent person to determine the feasibility and safety of providing fall protection for employees erecting or dismantling supported scaffolds. Each scaffold and scaffold component must support, without failure, its own weight and at least 4 times the maximum intended load applied or transmitted to it. Scaffolds must be designed by a qualified person and constructed and loaded in accordance with such design. Scaffolds and scaffold components must not be loaded in excess of their maximum intended loads or rated capacities, whichever is less.
The scaffold platform must be planked or decked as fully as possible with the space between the platform and uprights not more than 1 inch wide. When side brackets or odd shaped structures result in a wider opening between the platform and the uprights, the space must not exceed 9.5 inches.
The platform must not deflect more than 1/60 of the span when loaded.
The work area for each scaffold platform and the walkway must be at least 18 inches wide. When the work area must be less than 18 inches wide, guardrails and/or personal fall arrest systems must be used.
Access must be provided when the scaffold platforms are more than 2 feet above or below a point of access. Direct access is acceptable when the scaffold is not more than

14 inches horizontally and not more than 24 inches vertically from the other surfaces.


Crossbraces must not be used as a means of access.
A competent person must inspect scaffolds, scaffold components, and ropes on suspended scaffolds before each work shift and after any occurrence that could affect the structural integrity. He or she also must ensure that prompt corrective action is taken.
Stilts may be used on a large area scaffold. (A large area scaffold is a pole, tube and coupler, systems or fabricated frame scaffold erected over substantially the entire work area.) When a guardrail system is used, the guardrail height must be equal to the height of the stilts. Any alterations to the stilts must be approved by the manufacturer.
Bricklaying

Employees doing overhand bricklaying from a

supported scaffold must be protected by a guard-rail or personal fall arrest system on all sides except the side where the work is being done.
Erectors and Dismantlers

Employers must provide safe means of access for each employee erecting or dismantling supported scaffolds where the provisions of safe access is feasible and does not create a greater hazard. The determination must be made by a competent person based on his or her analysis of the site conditions.


Fall Arrest Systems

Personal fall arrest systems include harnesses, and components of the harness belt, such as Dee-rings, snaphooks, lifelines, and anchorage points. Vertical or horizontal lifelines may be used.


Lifelines must be independent of support lines and suspension ropes and must not be attached to the same anchorage points as the support or suspension ropes,
When working from an aerial lift, the lanyard must be attached to the boom or basket.

When lanyards are connected to horizontal lifelines or structural members on single or two point adjustable scaffolds, the scaffold must be equipped with additional independent support lines that are equal in number and strength to the suspension lines and have automatic locking devices.


Guardrails

Guardrails systems must be installed along all open sides and ends of platforms. Guardrails systems must be installed before the scaffold is released for use by employees other than erection/dismantling. Guardrails are not required on the front edge of a platform if the front edge of the platform is less than 14 inches from the face of the work, when plastering and lathing is being done 18 inches or less from the front edge, and when outrigger scaffolds are 3 inches or less from the front edge.


The height of the toprail for scaffolds can be between 38 inches and 45 inches. Midrails must be installed approximately halfway between the toprail and the platform surface.
When screens and mesh are used, they must extend from the top edge of the guardrail system to the scaffold platform and along the entire opening between the supports.
Crossbracing is not acceptable as an entire guardrail system; but crossbracing is acceptable for a toprail when the crossing point of the two braces is between 38 inches and 48 inches above the work platform. Crossbracing is also acceptable for

midrails when between 20 inches and 30 inches above the work platform. The end points of the crossbracing must be no more than 48 inches apart vertically.


Planking

Scaffold planking must be capable of supporting, without failure, its own weight and at least 4 times the intended load. Solid sawn wood, fabricated planks, and fabricated platforms may be used as scaffold planks following the manufacturer, a lumber grading association, or an inspection agency’s recommendations

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Supported Scaffolds

Supported scaffolds are platforms supported by legs, outrigger beams, brackets, poles, uprights, posts, frames, or similar rigid supports. The structural members—poles, legs, posts, frames, and uprights—must be plumb and braced to prevent swaying and displacement. Supported scaffold poles, legs, posts, frames, and uprights must be bear on base plates and mud sills, or other adequate firm foundations.


Supported scaffolds with a height to base width ratio of more than four to one must be restrained from tipping by guying, tying, bracing or equivalent means.
Guys, ties, and braces must be installed according to the scaffold manufacturer’s recommendations or at the closest horizontal member to the 4:1 height and be repeated vertically at locations of horizontal members every 20 feet or less thereafter for scaffolds 3 feet wide or less, and every 26 feet or less thereafter for scaffolds greater than 3 feet wide. The top guy, tie or brace of completed scaffolds must be placed no further than the 4:1 height from the top. Such guys, ties and braces must be installed at each end of the scaffold and at horizontal intervals not to exceed 30 feet (measured from one end [not both] towards the other).
Suspension Scaffolds

A suspension scaffold means one or more platforms suspended by ropes or other non-rigid means from an overhead structure. Each employee on a scaffold more than 10 feet above a lower level must be protected by guardrails, a personal fall arrest system, or both.

Fall arrest and guardrail systems must be used when working on single and two point adjustable suspension scaffolds and on self-contained adjustable scaffolds that are supported by ropes.
A competent person must inspect the ropes for defects prior to each workshift and after every occurrence that affect a rope’s integrity, evaluate the direct connections that support the load, and determine if two point and multi-point scaffolds are secured from swaying.
The use of repaired wire rope is prohibited. Drum hoists must contain no less than 4 wraps of the rope at the lowest point. All support devices must rest on surfaces capable of supporting at least 4 times the load imposed on them by the scaffold when operating at the rated load of the hoist (or at least 1.5 times the load imposed on them by the scaffold at the stall capacity of the hoist, whichever is greater). The stall load of any scaffold hoist must not exceed 3 times its rated load. The stall load is the load at which the prime-mover of a power-operated hoist stalls or the power to the prime-mover is automatically disconnected.
When scaffold platforms are more than 24 inches above or below a point of access, ladders, ramps, walkways or similar surfaces must be used. When using direct access, the surface must not be more than 24 inches above the surface or 14 inches horizontally from the surface.
Counterweights, used to balance adjustable suspension scaffolds, must be capable of resisting at least 4 times the tipping moment imposed by the scaffold operating at the rated load of the hoist, or 1.5 (minimum) times the tipping moment imposed by the scaffold operating at the stall load of the hoist, whichever is greater.
Only those items specifically designed as counterweights must be used. Counterweights used for suspended scaffolds must be made of materials that cannot be easily dislocated. Counterweights must be secured by mechanical means to the outrigger beams.
Vertical lifelines must not be fastened to counterweights. Sand, gravel, masonry units, rolls of roofing felt, and other such materials must not be used as counterweights.
A single tie back must be installed perpendicular to the face of the building or structure. Two tie backs installed at opposing angles are required when perpendicular tie back cannot be installed. Tiebacks must be secured to a structurally sound anchorage on the building or structure. Tie backs must not be secured to standpipes, vents, other piping systems, or electrical conduits.
Training

Each employee who performs work on a scaffold must be trained by a person qualified to recognize the hazards associated with the type of scaffold used and to understand the procedures to control or minimize those hazards. The training must include such topics as the nature of electrical hazards, fall hazards, falling object hazards, the maintenance and disassemble of the fall protection systems; the use of the scaffolds, handing of materials, and the maximum intended load carrying capacity. Employers who erect, disassemble, move, operate, repair, maintain, or inspect a scaffold must be trained by a competent person. The training must include such topics as the nature of the hazards, and the correct procedures for erecting, disassembling, moving, operating, repairing, inspecting, and maintaining the type of scaffolds in use. Recommended training includes erection and dismantling planning, personal protective equipment, access, guys and braces,

and parts inspection.

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Stairs


A stairway or ladder must be provided at all worker points of access where there is a break in elevation of 19 inches or more and no ramp, runway, sloped embankment, or personnel hoist is provided. Except during construction of the actual stairway, skeleton metal frame structures and steps must not be used (where treads and/or landings are to be installed at a later date), unless the stairs are fitted with secured temporary treads and landings.
When there is only one point of access between levels, it must be kept clear to permit free passage by workers. If free passage becomes restricted, a second point of access must be provided and used
When there are more than two points of access between levels, at least one point of access must be kept clear. All stairway and ladder fall protection systems must be provided and installed as required by the stairway and ladder rules before employees begin work that requires them to use stairways or ladders and their respective fall protection systems.
Stairways that will not be a permanent part of the structure on which construction work is performed must have landings at least 30 inches deep and 22 inches wide at every 12 feet or less of vertical rise.
Stairways must be installed at least 30 degrees, and no more than 50 degrees, from the horizontal. Where doors or gates open directly onto a stairway, a platform must be provided, and the swing of the door must not reduce the effective width of the platform to less than 20 inches
Except during construction of the actual stairway, stairways with metal pan landings and treads must not be used where the treads and/or landings have not been filled in with concrete or other material, unless the pans of the stairs and/or landings are temporarily filled in with wood or other material. All treads and landings must be replaced when worn below the top edge of the pan.
Stairways having four or more risers, or rising more than 30 inches in height whichever is less, must have at least one handrail. A stairrail also must be installed along each unprotected side or edge. When the top edge of a stairrail system also serves as a handrail, the height of the top edge must not be more than 37 inches nor less than 36 inches from the upper surface of the stairrail to the surface of the tread in line with face of riser at forward edge of tread. Midrails, screens, mesh, intermediate vertical members, or equivalent intermediate structural members must be provided between the top rail and stairway steps of the stairrail system.

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Midrails, when used, must be located midway between the top of the stairrail system and the stairway steps. The height of handrails must not be more than 37 inches or less than 30 inches from the upper surface of the handrail to the surface of the tread in line with face of riser at forward edge of tread.


The height of the top edge of a stairrail system used as a handrail must not be more than 37 inches nor less than 36 inches from the upper surface of the stairrail system to the surface of the tread in line with face of riser at forward edge of tread.
Temporary handrails must have a minimum clearance of 3 inches (7.62 centimeters) between the handrail and walls, stairrail systems, and other objects. Unprotected sides and edges of stairway landings must be provided with guardrail systems.

Storage


All materials stored in tiers must be secured to prevent sliding, falling, or collapsing.

Aisles and passageways must be kept clear and in good repair. Storage of materials must not obstruct exits. Materials must be stored with due regard to their fire characteristics.



Tire Cages


A safety tire rack, cage, or equivalent protection must be provided and used when inflating, mounting, or dismounting tires installed on split rims, or rims equipped with locking rings or similar devices.

Toeboards


Toeboards, when used to protect workers from falling objects, must be erected along the edge of the overhead walking/working surface. A standard toeboard must be at least 3-1/2 inches in height and may be of any substantial material either solid or open, with

openings not to exceed 1 inch in greatest dimension.



Toilets


Toilets must be provided according to the following: 20 or fewer persons—one facility; 20 or more persons—one toilet seat and one urinal per 40 persons; 200 or more persons—one toilet seat and one urinal per 50 workers. This requirement does not apply to mobile crews having transportation readily available to nearby toilet facilities.

Underground Construction


The employer must provide and maintain safe means of access and egress to all workstations. The employer must control access to all openings to prevent unauthorized entry underground.
Unused chutes, manways, or other openings must be tightly covered, bulkheaded, or fenced off, and must be posted with signs indicating “Keep Out” or similar language. Complete or unused sections of the underground facility must be barricaded.
Unless underground facilities are sufficiently completed so that the permanent environmental controls are effective and the remaining construction activity will not cause any environmental hazard or structural failure within the facilities,

the employer must maintain a check-in/check-out procedure that will ensure that aboveground designated personnel can determine an accurate count of the number of persons underground in the event of an emergency.


All employees must be instructed to recognize and avoid hazards associated with underground construction activities. Hazardous classifications are for “potentially gassy” and “gassy” operations. The employer must assign a competent person to perform all air monitoring to determine proper ventilation and quantitative measurements of potentially hazardous gases. Fresh air must be supplied to all underground work areas in sufficient quantities to prevent dangerous or harmful accumulation of dust, fumes, mists, vapors, or gases.

Wall Openings


Each employee working on, at, above, or near wall openings (including those with chutes attached) where the outside bottom edge of the wall opening is 6 feet or more above lower levels and the inside bottom edge of the wall opening is less than 39 inches above the walking/working surface must be protected from falling by the use of a guardrail system, a safety net system, or a personal fall arrest.
When an employee is exposed to falling objects, the employer must ensure that each employee wear a hard hat and erect toeboards, screens, or guardrail systems; or erect a canopy structure and keep potential fall objects far enough from the edge of the higher level; or barricade the area to which objects could fall.

Washing Facilities


The employers must provide adequate washing facilities for employees engaged in operations involving harmful substances. Washing facilities must be near the worksite and must be so equipped as to enable employees to remove all harmful substances.

Welding, Cutting, and Heating


Employers must instruct employees in the safe use of welding equipment. Proper precautions (isolating welding and cutting, removing fire hazards from the vicinity, providing a fire watch) for fire prevention must be taken in areas where welding or other “hot work” is being done. No welding, cutting, or heating must be done where the application of flammable paints, or the presence of other flammable compounds or heavy dust concentrations creates a fire hazard. Arc welding and cutting operations must be shielded by noncombustible or flameproof screens to protect employees and other persons in the vicinity from direct arc rays. When electrode holders are to be left unattended, the electrodes must be removed and the holder must be placed or protected so that they cannot make electrical contact with employees or conducting objects.
All arc welding and cutting cables must be completely insulated and be capable of handling the maximum current requirements for the job. There must be no repairs or splices within 10 feet of the electrode holder, except where splices are insulated equal to the insulation of the cable. Defective cable must be repaired or replaced.

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Fuel gas and oxygen hose must be easily distinguishable and must not be interchangeable. Hoses must be inspected at the beginning of each shift and must be repaired or replaced if defective.


General mechanical ventilation, local exhaust ventilation, airline respirators, and other protection must be provided, when welding, cutting or heating:
• Zinc-, lead-, cadmium-, chromium-, mercury-, or materials bearing, based, or coated with beryllium in enclosed spaces;
• Stainless steel with inert-gas equipment;
• In confined spaces; and where an unusual condition can cause an unsafe accumulation of contaminants.

Wire Ropes, Chains, and Ropes


Wire ropes, chains, ropes, and other rigging equipment must be inspected prior to use and as necessary during use to ensure their safety. Defective gear must be removed from service.
Job or shop hooks and links or makeshift fasteners formed from bolts, rods, or other such attachments must not be used.
When U-bolts are used for eye splices, the U-bolt must be applied so that the “U” section is in contact with the dead end of the rope. When U-bolt wire rope clips are used to form eyes, the following table must be used to determine the number and spacing of clips.
Woodworking Machinery
All fixed power-driven woodworking tools must be provided with a disconnect switch that can be either locked or tagged in the off position. All woodworking tools and machinery must meet applicable requirements of ANSI 01.1-1961, Safety Code for woodworking machinery.
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