Millions of construction workers work on scaffolds. Protecting these workers from the hazards associated with scaffolds is a key concern on today’s jobsite. Since 1971, the Occupational Health and Safety Administration (OSHA) has put a standard in place to help protect workers on scaffolds. Most of the time, workers are injured in scaffold accidents because the planking or support gave way, or the worker slipped or was struck by a falling object. Among these reasons, plank slippage was the most commonly cited. In some cases, a scaffold accident is more serious, potentially causing a fatality. In the years 2000 to 2004, OSHA cited that an average of 88 fatalities occurred from scaffolds and staging. This number accounts for approximately 9% of all fatalities that occur in the construction industry, making scaffolds a serious risk to workers.
By adhering to OSHA standards, homebuilders can help protect workers on scaffolds. Builders have paid significant penalties for failing to make sure workers are safe. With some effort, builders can avoid these penalties-checking scaffolds for problems and getting them corrected makes it possible to avoid injuries and fatalities.
Safe rails and platforms
If the scaffold is 10′ or higher above a lower level, top rails, midrails, and toeboards should be installed on all open sides of the scaffold platform. Rails should be made from 2x4s or the equivalent, and they should be 38″ to 45″ high. The rails should be able to withstand 200 pounds being thrown against them. Midrails should be halfway between the top rails and the platform. Toeboards should be able to withstand a force of at least 50 pounds, and they should be a minimum of 3 ½” high from the top edge to the level of the working surface.
Platforms should consist of undressed 2x10s that have been properly inspected and graded. The maximum allowable gap between planks is 1″. The ends of the platforms must be cleated, be restrained, or extend at least 6″ over the centerline of support. If a platform is more than 10′ long, the ends shouldn’t extend over their supports more than 18″. If a platform is 10′ or fewer long, the ends shouldn’t extend over their supports more than 12″.
Safe scaffold access
All workers must be able to safely access any level of a scaffold that’s 2′ above or below an access point. They shouldn’t have to use the cross braces to enter or exit the platform. An attachable ladder or other means of access is required when the distance from one surface to the next is more than 2′. The ladder should be positioned so that the bottom rung isn’t more than 2′ above the worker’s starting point.
The base section of a scaffold has to be stable. It’s impossible to erect a safe scaffold if the base rests on items like barrels, boxes, loose bricks, or concrete blocks. These items are unstable and unlikely to provide a level foundation. Instead, scaffolds should be set on base plates, mud sills, or other items that provide an adequately firm foundation. The footings should be capable of supporting the loaded scaffold without settling or moving.
No matter how stable the base, the scaffold won’t be safe if the work platform doesn’t remain upright. As a general rule, a scaffold becomes unstable once its height reaches 4 times its width. If the scaffold is 4 times as high as its base is wide, outriggers should be installed to increase the scaffold’s width. An alternative to installing outriggers is to tie the scaffold to the structure under construction to keep it from tipping. If guys or ties are used, they should be installed on the horizontal member closest to the 4:1
width-to-height point. There should be a guy or tie every 20′ up for scaffolds up to 3′ wide and every 26′ up for scaffolds more than 3′ wide.
OSHA states that scaffolds can be erected, moved, dismantled, 棚架費用 or altered only under the supervision and direction of a “competent person.” A “competent person” is someone who can identify hazards and is authorized to take prompt action to eliminate them. This individual should also inspect the scaffolds each day before workers use them and after anything happens to the scaffolds that could undermine their integrity.
It’s important to not allow excessive debris and equipment to accumulate on or around the scaffold. Workers should have pulleys for pulling tools and equipment up and down the scaffold, leaving their hands free to climb access ladders. Don’t allow anyone to work on scaffolds during storms or in high winds, and don’t allow anyone to move a scaffold while workers are on it unless it’s been designed for that purpose. Repair, replace, or remove any damaged scaffold parts.