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We normally are capable of testing ground ladders in conjunction with the inspection of aerials and platforms, therefore the amount of downtime to the equipment is reduced. Combine all these elements together and you end up with an inspection program that will insure the safety of your ground ladders. All ground ladders inspected
by STI are done so in accordance with NFPA 1932:
Visual Inspection The following areas are visually inspected prior to any other ladder test.
Structural Inspection Horizontal Bending Test
For all ladders except pompier ladders, the following test procedures are used:
The ladder shall be placed in a flat horizontal position supported under the first rung from each end of the ladder. Extension and combination ladders shall be extended to their maximum extended length with pawls engaged for this test.
Procedures for Metal and Fiberglass Ladders
Step 1. The ladder shall be loaded with a preload. The load shall be allowed to remain for at least 1 (one) minute to “set” the ladder prior to completing the entire test.
Step 2. After removing the preload, the distance between the bottom edge of each side rail and the surface upon which the ladder supports are placed shall be measured. All measurements shall be taken at a consistent location and near as practical to the center of the ladder.
Step 3. The ladder test load shall be applied equally to the center span over a specified distance from the center. The test load shall remain in place for 5 (five) minutes.
Step 4. The test load shall then be removed and the distance between the bottom of each side rail and surface upon which the ladder supports are placed shall be measured.
Differences between measurements taken in Step 2 and Step 4 shall not exceed specifications. There shall be no visible permanent change or failure of any hardware.
Ladder Hardware Test (Extension Only)
The ladder is placed in a flat horizontal position, extended to a minimum of 1 (one) rung beyond the bedded position. A test load is placed on the ladder in such a manner as to subject the lock hardware to a 1000 (thousand) LBS. load. The test load is applied for a period of 1 (one) minute. The ladder shall sustain this test load with no permanent deformation or other visible weakening of the structure.
Ladder Hook Test
The ladder hook angle relative to the ladder side rail is recorded. A load of 1000 (thousand) lbs is then applied to the hook tip, parallel to the ladder side rails. The test load is maintained for 1 (one) minute. The test load is then removed and the roof hook angle relative to the ladder side rail is again measured.
No visible deformation is permitted.
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