Chapter 18. Walking and Working Surfaces

I. In general, all areas of the workplace should be kept clean, orderly, sanitary, and as dry as possible. These guidelines apply to work areas, passageways, store rooms, and service rooms. All spills should be cleaned promptly. Floors in work areas must be kept free of scraps, chips, oil spills, and other debris.

II. Areas which are constantly wet should have non-slip surfaces or mats where workers may walk or work. Where wet processes are used good drainage must be maintained.

III. Every floor, working place, and passageway must be maintained free from protruding nails, splinters, holes, and loose boards.

IV. Where mechanical handling equipment is used, such as lift trucks, sufficient safe clearance must be provided for foot and vehicular traffic.

V. Aisles. No obstructions that could create a hazard are permitted in aisles. All permanent aisles must be easily recognizable.

VI. Guard rails and toe boards. As a general condition, a standard toe board and guard rail are required where ever people walk near or beneath the open sides of a platform or similar structures; where things could fall from a structure; or where things could fall from a structure into machinery below.

A. A standard guard railing consists of a top rail and post. The nominal distance from the upper surface of the top rail to the floor, platform runway, or ramp should be 42 inches. There must be an intermediate rail spaced approximately halfway between the top of the rail and the floor.

B. All handrails and railing must have a clearance of at least one and one half inches between the handrail or railing and any other object.

C. A standard guard railing should withstand at least 200 lbs., applied in any direction at any point on the top rail.

D. For wood railings, the rail and posts must be at least two-by-four inch stock with the posts spaced not more than six feet apart. For pipe railings, rails and posts must be at least one and one half inch (outside diameter) pipe with posts spaced not more than eight feet apart. For structural steel posts, posts and rails must be two-by-two-by-three eighths inch angles or other metal shapes of equivalent strength with posts spaced not more than eight feet apart.

E. Toeboards. Standard toeboards must be approximately four inches in height from the floor to the top edge with no more than one quarter inch gap between the toeboard and the floor. The toeboard may be constructed of any solid or perforated material as long as the openings are smaller than one inch. The purpose of a toeboard is to keep tools and small objects from falling to workers below.

VII. Ladders.

A. Fixed ladders should be designed to withstand a single concentrated load of at least 200 lbs. Rungs of metal ladders must have minimal diameter of three quarters inch. Rungs must be at least 16 inches wide, be spaced 12 inches apart, and be free of splinters and burrs. Ladders, when their location so demands, must be painted or treated with a preservative to resist deterioration.

B. The preferred pitch for a safe descent is 75 to 90 degrees. Ladders with 90 degree pitch must have two and one half feet of clearance on the climbing side. There must be a three foot clearance on ladders with a 75 degree pitch. There must be a least a seven inch clearance in back of the ladder to provide adequate toe space.

C. Fixed ladders must have cages if they are longer than 20 feet. Landing platforms must be provided on ladders greater than 20 feet long. A platform is required every 30 feet for caged ladders and every 20 feet for unprotected ladders.

D. Siderails must extend at least three and one half feet above the landing. There must be a clear width of 15 inches on each side of the center line of the ladder, unless the ladder is equipped with a cage or well.

E. Fixed ladders that are not equipped with cages or other forms of worker fall protection may be used as a means of access for firefighters or other emergency personnel. However, adequate measures must be taken to prevent non-emergency use of such ladders. Appropriate controls include the use of barriers and signs.

F. Portable ladders must be maintained in good condition at all times with tight joints, securely attached hardware and fittings, and freely operating movable parts. They must be inspected frequently. Defective ladders must be removed from service for repair or destruction.

G. Step ladders must be equipped with a metal spreader or locking device of sufficient size and strength to securely hold the front and back sections in open positions.

H. Ladders should be stored where they will not be exposed to the elements. Metal ladders must not be used energized electrical equipment.

I. All ladders must be placed so that they have a secure footing. They may not be placed on boxes, barrels, bricks, or other unstable bases to obtain additional height. Non-slip bases should be used.

J. Workers should not use pallets, boxes, or other stacked materials for climbing. Step stools or ladders should be used to reach materials above shoulder height.

VIII. Fixed industrial stairs.

A. Riser height and tread width of fixed industrial stairs should be uniform throughout any flight of stairs. All treads must be reasonably slip resistant.

B. The minimum permissible width of a stairway is 22 inches. If the stairway is a means of exit access, it must be at least 28 inches wide.

C. The angle to the horizontal made by the stairs must be between 30 and 50 degrees.

D. All stairs should be adequately lighted.

E. If the tread is less than nine inches wide the risers should be open.

F. Flights of stairs having four or more risers require the following:

1. A stair railing is required on each opened side.

2. If the stairway is less than 44 inches wide and both sides are enclosed, at least one handrail is required, preferably on the right side descending.

3. If the stairway is greater than 44 inches wide a handrail is required on each enclosed side.

4. If the stairway is greater than 88 inches wide an intermediate stair railing located midway is required.

G. The vertical height of a stair railing must be 30 to 34 inches, and it must be of construction similar to the standard guard railing.

H. Spiral stairways are not permitted except for special limited usage and secondary access situations where it is not practical to provide a conventional stairway.

IX. Fixed steps.

A. Individual steps used for access or egress, embedded in the walls of risers or the conical top sections of manholes must be safe, well constructed, and installed in accordance with good engineering practices.

B. Individual rungs or steps must be uniformly spaced from 12 to 16.5 inches.

C. The use of manhole steps in manholes should be designed to prevent the foot from sliding off the end.

X. Alternating tread stairs.

A. Alternating tread type stairs are permitted if they are installed, used, and maintained according to the manufacturer's recommendations and three design requirements.

B. The specific design requirements are:

1. The stair must be installed at an angle of 70 degrees or less.

2. The stair must be capable of withstanding a minimum uniform load of 100 lbs. per square foot with a design factor of 1.7. The tread must be capable of carrying a minimum concentrated load of 300 lbs. at the center of any tread span or exterior arc with a design factor of 1.7. If the stair is intended for greater loading, construction must allow for that loading.

3. The stairs must be equipped with a handrail at each side to assist the workers in climbing or descending.