Ladder and scaffold are used to perform work in elevated locations. Any time that work is performed above ground level, there is an increased chance that an accident will occur.
Basically, there are three types of ladders commonly found at work sites: straight ladders, extension ladders, and stepladders.
The straight ladder consists of two rails, rungs between the rails, and safety feet on the bottoms of the rails.
The straight ladders used at work sites are usually made of wood or fiberglass. There are also metal ladders, but metal conducts electricity, so a metal ladder could be hazardous to use around electrical equipment. Dry wood and fiberglass do not conduct electricity.
OSHA requires regular inspections of all ladders, and an inspection before each use. The following guidelines apply to inspecting and using a ladder:
- Examine the rails and rungs for cracks and other damage, and check for loose rungs.
- Check the entire ladder for loose nails, screws, brackets, and other hardware.
- If any hardware problems are found, tighten loose parts or have the ladder repaired before use.
- Do not use a damaged ladder.
- Place ladders at a proper angle. The distance between the bottom of the ladder and the base of the structure it is leaning against should be at least1/4th of the vertical height. The vertical height is the distance between the ground and the point where the ladder contacts the structure.
- To ensure a proper distance between the bottom of the ladder and the base of the structure place your feet at the bottom of the ladder and reach straight out with your hands. If the distance is correct, you should be able to just touch the ladder’s rails.
- Before stepping off of ladder onto a platform or roof, make sure that the top of the ladder extends at least 3 feet above the point where the ladder contacts the structure.
- When a ladder must be set up on soft or sandy soil, place a wide board under the feet to keep them from sinking into the ground.
- If a ladder must be placed in front of a door that opens towards the ladder, the door should be locked or blocked open.
- When climbing a ladder, keep both hands on the rails and your body’s weight in the enter of the ladder between the rails.
- When climbing a ladder, make sure you face the ladder at all times.
- Never try to move a ladder while you are on it by walking the ladder. Always climb down first, then move the ladder.
Another commonly used type of ladder is actually two straight ladders connected. That type of ladder is an extension ladder.
The two straight ladders that make up an extension ladder are assembled using a mechanism that allows the overlap between them to be varied. This makes it possible to vary the length of an extension ladder to match the needs of a particular job. An extension ladder also has rung locks that support the weight of the movable section and a person climbing on the movable section.
An extension ladder should be inspected for many of the same things as a straight ladder. The rope, rungs, and rung locks should be checked for loose rungs and signs of damage. The rope that is used to raise and lower the movable section of the ladder should be checked to see if it is frayed or has worn spots. A frayed or worn rope should be replaced. The rung locks should be carefully inspected for damage before each use. If damage is found, the rung lock should be replaced or repaired before the ladder is used.
Extension ladders are positioned and secured the same way that straight ladders are.
When the length of an extension ladder is adjusted, the movable section should be repositioned from the bottom, not the top. After an adjustment is made, it is important to be sure that the rung locks are properly engaged. To ensure its strength, an extension ladder needs a certain amount of minimum overlap between its sections. For example, ladders up to 36 feet long must have an overlap of at least 3 feet. Ladders 36 to 48 feet long require at least 4 feet of overlap, and for ladders that are 48 to 60 feet long, 5 feet is needed.
Another type of ladder is a stepladder. Stepladders are self-supporting ladders made up of two sections that are hinged at the top.
The section of a stepladder that is used for climbing consists of rails and rungs similar to those found on straight ladders. The other section consists of rails and braces. The braces should never be used for climbing.
The two sections of a stepladder are also connected by spreaders, which are hinged arms used to position the ladder for stability and to prevent it from folding while it is in use.
Stepladders should be inspected the same way that straight ladders and extension ladders are checked. Particular attention should be paid to the hinges and the spreaders to make sure that they are in a good state of repair.
When a stepladder is placed in position, all four feet must be on a hard, even surface. If they’re not, the ladder can rock from side to side or corner to corner when someone climbs it. With the ladder in position, the spreaders should be checked to make sure that they are locked in the fully open position.
When a stepladder is being used, the user should never stand on the top step or climb the back of the ladder. It is important not to stand on the top step of a stepladder because putting a person’s weight that high will make the ladder unstable. The top of a stepladder is made to support the hinges, not to be used as a step. And, although the rear braces may look like rungs, they are not designed to support a person’s weight, so no one should climb the back of a stepladder.
Like ladders, scaffolds are used to work in an elevated location. Scaffolds provide safe, secure, elevated work platforms for workers and materials.
Scaffolds are designed and built to high safety standards, but normal wear and tear or accidental overstress can weaken a scaffold and make it unsafe to use. For this reason, it is important to inspect all parts of a scaffold before each use.
There are three basic types of scaffolds: tubular welded, or sectional, scaffolds; rolling scaffolds; and suspended scaffolds.
Sectional scaffolds are made of steel, stainless steel, or aluminum. This makes them stronger and more fire-resistant than wooden scaffolds.
A rolling scaffold is essentially a sectional scaffold that has wheels on its legs so that it can be moved. The wheels are fitted with brakes to prevent movement when work is in progress.
A suspended scaffold is a platform supported by ropes or cables attached to the top of some support structure. The cables may also be attached to beams extending out of the side of a support structure. The platform is raised or lowered by pulling on the suspension ropes or cables by hand or with a motor.
Anyone who is working on a suspended scaffold should be wearing a safety harness. The lanyard should be attached tan independent lifeline, and not to the scaffold.
Any scaffold that is assembled for use should be tagged. The color of the tag indicates the condition of the scaffold. A green tag identifies a scaffold that has met all OSHA standards and is safe to use. A yellow tag means a scaffold does not meet all applicable standards and should not be used. A red tag means that the scaffold is being erected or taken down and should not be used.
All scaffolds should be inspected before use. Any problems must be corrected before a scaffold is used. Scaffolds should be checked for bent, broken, or badly rusted tubes. They should also be checked for loose joints where tubes are connected. The scaffold’s weight limit should be compared to the total weight of the personnel, tools, equipment, and material expected to be placed on the scaffold. Scaffold weight limits should never be exceeded. When a scaffold must be set up on soft or sandy soil, a wide board should be placed under the feet to keep them from sinking into the ground.