SECTION 18. WALKING AND WORKING SURFACES

18.1 GENERAL REQUIREMENTS

Housekeeping - it is imperative buildings be kept clean, orderly and in sanitary condition. A major cause for fires and accidents is poor housekeeping.

Aisles - permanent aisles must be sufficiently wide to allow for proper emergency egress; refer to Section 9, titled “Means of Egress from Buildings.”

Covers and Guardrails - open pits, vats, tanks, ditches, drop-offs, etc., must have covers or guardrails to protect personnel.

18.2 GUARDRAILS

A standard guardrail consists of top rails, mid-rail, and toe kick board. The top rail must be 42 inches high. The guardrail structure must be able to withstand a force of 200 lbs. exerted in any direction at any point.

18.3 PORTABLE LADDERS

All portable ladders will meet ANSI standards.

The use of step or platform ladders longer than 12 feet, extension ladders longer than 17 feet working length, or straight ladders longer than 20 feet is discouraged.

Ladders will be maintained in good condition at all times; the joint between the steps and side rails will be tight, the safety feet and other hardware and fittings securely attached, and the moveable parts will operate freely without binding or undue play.

Users are responsible for inspecting every ladder they use prior to each use. If any defects, including broken parts, are found the ladder will not be used. A defective ladder will be withdrawn from service and tagged “Dangerous, Do Not Use”. Damaged ladders will be destroyed.

18.4 FIXED LADDERS

The minimum live load design will be at least 200 lbs. exerted to provide maximum stress.

Metal rungs will be a minimum of 1-inch diameter by 16 inches long. The distance between rungs will not exceed 12 inches.

Rungs, cleats, and steps will be free of splinters, sharp edges, burrs, or other projections. All ladders will be inspected regularly.

The clearance for fixed ladders on the climbing side will range a minimum of 36 inches on a 76-degree ladder slope to 30 inches on a 90-degree ladder slope.

A clear way at least fifteen inches on each side of the centerline will be maintained, except where cages or wells are necessary.

The clearance from the rung to the nearest object back will be at least 7 inches.

All fixed ladders between 20 feet and 30 feet in unbroken lengths will have cages that extend between 7 and 8 feet from the ladder base, or a fixed rail climbing system.

Side rails of through- or side-step ladders will extend 3 1/2 feet above parapets or landings.

The preferred pitch for fixed ladders will be within 75 degrees and 90 degrees from the horizontal.

All portable ladders must be the proper length for the job; no attempt will be made to artificially extend it by splicing, or by placing it on a box, barrel, or other object.

A ladder must be placed so that it has firm footing and its feet are level.

The feet of a straight or extension ladder must be set back a safe distance from the vertical - one-fourth the working length of the ladder. Ladders used to access a walking surface or roof must extend at least 36 inches above the landing.

Both rails at the top of an extension or straight ladder must rest against a firm and stationary object. The ladder will be tied off at the top or bottom, or otherwise secured while being used.

Extension ladder locks must be securely hooked over rungs before climbing. Step or platform ladders must be fully opened with their spreaders locked before climbing.

Folded step or platform ladders will not be used in lieu of extension or straight ladders.

Users must be sure their shoes are free of grease, oil, mud, paint, snow, or other slippery substances that could cause a slip or fall.

Users must face the ladder when ascending or descending, taking one step at a time.

Users must keep both hands free while ascending or descending a ladder. One hand shall be in contact with the ladder at all times. Small tools or other items may be carried in pockets, or tool pouches, or attached to a tool belt. Larger items may be raised or lowered by the use of a bucket and/or hand line.

Users must never overextend their body on a ladder. The ladder must be moved so work can be accomplished without reaching too far to one side. Overreaching causes imbalance, resulting in the user falling.

Only one person will be on a ladder at one time, unless the ladder is designed and rated for two.

Users must never stand on the top two steps of a stepladder.

Ladders that project into doorways or other areas of personnel/vehicular traffic must be protected by barricades or by someone posted to stop or direct traffic.

Metal or wet wood ladders conduct electricity and will not be used for electrical work or in areas where they could contact energized conductors.

Ladders will not be used as supports for planks or in the horizontal position for any purpose.

Under no circumstances may cable trays be used as ladders.

“Homemade” ladders of ordinary lumber will not be used.

Ladder climbing should always use the 3-point contact method. Where the climber will maintain 3 points of contact at all times. Utilizing the 4th point to reposition during the climb.

18.5 SCAFFOLDS

There are many types of scaffolds and extensive codes and standards regarding their use. The use of all scaffolds will be reviewed and approved by the Site Safety Officer prior to their use. The Site Safety Officer will ensure the safety of erection, use, movement, and dismantling of scaffolds, as well as training of individuals using scaffolds.

18.6 MANLIFTS

Manlifts are preferred alternatives to ladders. While the Observatory does not own any, renting of these is strongly encouraged. Persons using the manlift must read and understand all of the instructions provided by the rental agency prior to use.

18.7 SUMMARY

Working surfaces are one of the most common sources of accidents. It is, therefore, extremely important all personnel involved in the use of ladders, scaffolds, stairs, etc., ensure such equipment meets minimum standards for safe construction and all safety procedures/rules are followed.