The Extension Trestle Ladder is a self-supporting portable ladder that is adjustable in length, consisting of a Trestle Ladder base and a vertically adjustable Extension section with a means for locking the ladders together. It is intended for use by one person.
An Extension Trestle Ladder base section ranges in length up to 20 feet as measured along the side rail. The Extension section length may not exceed the base section length. The highest standing level on an Extension Trestle Ladder is the second step below the top of the extension section, or slightly more than 2 ft from the top of the ladder. The highest standing level is required to be marked on the specifications label on the side rail. Therefore, when planning your job, the maximum work height is established by adding the user’s height and reach to the highest standing level.
Extension Trestle Ladder Extension Sections that are not equipped with anti-slip feet or any other provision necessary for compliance with Single Ladder requirements are required to be marked with a safety sign instructing that the Extension section is not to be used separately. In lieu of the safety sign, the Extension section must be held into the base section by permanently attached stops, i.e. stops that require some type of forcible means to achieve Extension Section removal.
When the Extension Section has previously been used as a Single Ladder, care should be exercised in properly reassembling it into the base section to insure that the interlocking guides or brackets are properly engaged before further use.
An Extension Trestle Ladder requires level ground support for all four of its side rails. If this worksite condition does not exist, an Extension Trestle Ladder should not be selected for the job.
An Extension Trestle Ladder must not be used unless its base is spread fully open and the Spreaders locked. Extension Trestle Ladders are not to be used as Single Ladders or in the partially open position.
In order to prevent tipping the ladder over sideways due to over-reaching, the user(s) must climb or work with the body near the middle of the steps or rungs. The ladder should be set-up close to the work. Never attempt to move the ladder without first descending, relocating the ladder, and then re-climbing. Do not attempt to mount the ladder from the side or step from one ladder to another unless the ladder is secured against sideways motion.
In an effort to avoid losing your balance and falling off the Extension Trestle Ladder, the user must not step or stand higher than the step indicated on the label marking the highest standing level.
When ascending or descending the ladder, always face the ladder and maintain a firm hand hold. Do not attempt to carry other objects in your hand(s) while climbing.
The anti-slip feet at the bottom of the base section side rails must be present and in good condition prior to using the ladder. The ladder must not be used on ice, snow or slippery surfaces unless suitable means to prevent slipping is employed.
An Extension Trestle Ladder must never be placed upon other objects such as boxes, barrels, scaffolds, or other unstable bases in an effort to obtain additional height.
A thorough inspection must be made when the ladder is initially purchased and each time it is placed into service. Clean the climbing and gripping surfaces if they have been subjected to oil, grease or slippery materials. Working parts, bolts, rivets, step-to-side rail connections, and the condition of the anti-slip feet (safety shoes) shall be checked.
Ladders exposed to excessive heat, as in the case of fire, may have reduced strength. Similarly, ladders exposed to corrosive substances such as acids or alkali materials may experience chemical corrosion and a resulting reduction in strength. Remove these ladders from service.
Broken or bent ladders, and ladders with missing or worn out parts must be taken out of service and marked, for example, “Dangerous – Do Not Use” until repaired by a competent mechanic or destroyed. No attempt shall be made to repair a ladder with a defective side rail. Ladders with bent or broken side rails must be destroyed.
In the event a ladder is discarded, it must be destroyed in such a manner as to render it useless. Another person must not be given the opportunity to use a ladder that has been deemed unsafe.
When transporting ladders on vehicles equipped with ladder racks, the ladders must be properly supported. Overhang of the ladders beyond the support points of the rack should be minimized. The support points should be constructed of material such as wood or rubber-covered pipe to minimize the effects of vibration, chafing and road shock. Securing the ladder to each support point will greatly reduce the damaging effects of road shock.
Storage racks for ladders not in use should have sufficient supporting points to avoid sagging which can result in warping the ladder. Other materials must not be placed on the ladder while it is in storage.
Extension Trestle Ladder Safety Standards
Safety requirements for Construction, Performance, Use and Care of Extension Trestle Ladders can be found in the following standards:
- ANSI A14.1 (Portable Wood Ladders)
- ANSI A14.2 (Portable Metal Ladders)
- ANSI A14.5 (Portable Reinforced Plastic Ladders)
The most current revision of each standard in the ladder family can be purchased at the ANSI webstore at http://webstore.ansi.org/.