Question and answer section
The three basic types of ladders are extension (straight), step and step/extension. Ladders are rated by load capacity, into household, commercial and industrial grades (see table).
Ladder rungs are either flat, round or “D” shaped. The minimum size considered acceptable for round rungs is 1-1/4″, 1-1/2″ for “D” rungs. To insure safety, rungs are required to be capable of carrying a much higher load than the rated load for the entire ladder.
When choosing a ladder, consider:
Type of activity involved: The type of activity dictates which type of ladder you’ll need. Use a stepladder for interior painting, drywalling, spackling and wallpapering. Stepladders include stepstools and platform ladders, generally for home or light commercial use. Stepladders are self-supporting and may include a pail hook or shelf. Extension ladders are best for painting exteriors, cleaning gutters, replacing shutters and siding, etc.
Demands of the application: Make sure the ladder is suitable for the physical demands of the application. The rated load capacity must exceed the maximum aggregate weight of the user along with his or her clothing and tools. Duty ratings are also color coded. Look for the proper duty ratings to match the highest level of use.
Height the ladder must reach: For a climber to work from a safe position, the ladder’s top should extend about 3 feet above the working surface when in use. Stepladders should be high enough for the user not to have to stand above the second step from the top. On extension ladders, stand no more than four rungs from the top.
Basic material: The most common ladder materials are wood, aluminum and fiberglass. Wood ladders are nonconductive when clean and dry. Wood also provides a natural firm grip for feet and hands. However, wood tends to be heavy, and is vulnerable to moisture/rot.
Aluminum is lightweight and strong, but does conduct electricity — aluminum ladders should never be used when working near energized electrical lines.
Fiberglass offers a blend of desirable qualities. It is non-conductive and strong — and excellent choice for a variety of circumstances.
Ladder safety tips
- Learn the proper methods for working with a ladder
- Keep your ladders well-maintained (for wood, treat with a wood preservative that leaves a clear surface)
- Choose duty ratings to match the highest level of use
- Use or repair a bent or damaged ladder
- Test a ladder by jumping on it
- Use a ladder on slippery surfaces or uneven ground
- Place ladder feet on power cords or come in contact with electrical current or power lines
- Climb down a ladder with your back to the ladder or carrying a load in your arms
- Overreach, lean to one side or stand on one foot
- Hurry or skip steps when getting on or off the ladder
- Leave a ladder unattended
- Position the ladder where it blocks foot traffic or where it could be bumped by a door
- Place the ladder on boxes, chairs, furniture or other moveable object to try to climb higher
- Climb from one ladder to another or try to move a ladder while on it
- Climb a ladder when ill or using drugs or alcohol
- Drop or throw ladders
- Paint a wooden ladder (paint hides damage and can create a slippery surface for climbing)
|Extension Ladder Length Chart|
|height to eaves||buy this length||max. working length|
|9-1/2′ to 13-1/2′||20′||17′|
|13-1/2′ to 17-1/2′||24′||21′|
|17-1/2′ to 21-1/2′||28′||25′|
|21-1/2′ to 25′||32′||29′|
|25′ to 28′||36′||32′|
|28′ to 31′||40′||35′|
|Ladder Duty Rating Table|
|GRADE||TYPE||RATED LOAD||COLOR CODE|
|Extra-Heavy-Duty Industrial||IA||300 LBS.||BLACK|
|Heavy-Duty Industrial||I||250 LBS.||BLUE|
|Medium-Duty Commercial||II||225 LBS.||YELLOW|
|Light-Duty Household||III||200 LBS.||RED|
– Hardware Hotline February, 2000
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