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Portable Ladder Safety Guide


Portable Ladder Advisory

Notice: Training materials found on these pages are provided for the use of Princeton University faculty, staff and students to meet training needs specific to Princeton University.


Portable ladders are used at Princeton University in a wide variety of settings, both academic and administrative. Misuse of portable ladders can result in serious injuries from falls or, in the case of metal ladders, electrical shock. Portable ladders must be maintained in good condition at all times, and inspected at regular, frequent intervals. This advisory gives some guidelines to proper selection, use and care of portable ladders.

There are two types of portable ladders: stepladders (A-frame) or straight (extension) ladders. Both types can also be made out of different materials, including metal, wood, or fiberglass. Metal ladders should never be used for work on or around exposed electrical elements; a wood or fiberglass ladder is necessary. However, refer to warning labels on the ladder or the manufacturer’s directions because some nonmetal ladders are reinforced with steel or other conductive materials.

Stepladders (top)

There are several key points for safe use of stepladders:

  • The spreaders should be fully extended and locked in place before use
  • The top two levels are not for sitting or standing.
  • The paint tray should only be used for holding paint cans and trays
  • The back of the ladder shouldn’t be used for climbing
  • Stepladders should never be leaned against a wall for use as a straight ladder.

Straight Ladders (top)

Length is extremely important in selecting the proper straight ladder. If the ladder is used to reach a roof or elevated platform, select one that can extend at least three feet above the point of support. Please refer to the table below to help in length selection.

Straight Ladder Length for Various Heights
Height to Reach (feet)
Recommended Ladder Height (feet)


Set up and placement of a ladder is also important in safe use. Straight ladders should be positioned so that the horizontal distance between the foot of the ladder and the support against which it is placed is equal to one-fourth the height of the ladder at the top point of support. This is demonstrated in the following illustration.

ladder example

Portable Ladder Climbing Guidelines (top)

There are a few climbing guidelines that help to prevent accidents when using a portable ladder. Wear shoes with nonskid soles that are free of mud or grease. Metal rungs can be very slippery in certain conditions. Just as you shouldn’t stand on the top or top step of a stepladder, you should also avoid standing higher than the third highest rung from the top of a straight ladder. This can make the ladder unsteady and leaves the user with no handhold.

Ladders should always be placed on stable bases. Boxes, barrels, or other unstable surfaces should never be used to obtain additional height.

If necessary, have another person hold the base of the ladder. This helps with stability as well as assistance in unloading objects from a height. If no one is available, the ladder should be securely lashed or fastened the ladder (top and bottom) to prevent it from slipping.

Overreaching can also cause instability. A good rule of thumb is to not let one’s belt buckle outside the uprights. Also, when climbing or descending ladders, always face the ladder and hold onto each side rail.

Ladders should be inspected on a regular basis. See the Ladder Inspection Checklist for what to look for during the inspection.

Storage and Maintenance (top)

Storage and maintenance of ladders need to be considered as well. It’s best to hang a ladder horizontally on wall hooks in a dry place not subject to extremes of temperatures. The user can do minor maintenance, like lubricating hinges and tightening hardware. However, ladder repair is specialized work and should be completed by qualified persons or the manufacturer.

If conditions exist that make a ladder unsafe for use, it should be removed from service immediately and marked with a warning such as "Dangerous – Do Not Use". If a ladder cannot be repaired, it should be destroyed.

For More Information (top)

If you have any questions about ladder safety, you can see the University Health and Safety Guide or call EHS at 8-5296.


For a disclaimer and information regarding the use of this page, see the disclaimer notice.
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