Construction Solutions - Adjustable Scaffolding for Masonry Work



Solution: Adjustable Scaffolding for Masonry Work
	E-mail this Solution to a Friend


	Description:	Adjustable tower scaffolding consists of independent base and tower sets, with an elevating carriage that moves masons and materials up the wall every one or two block courses. The carriage supports multi-level work platforms with separate decks for masons, laborers, and materials. Planks, materials, tools, and guardrail systems remain in place while the carriage is elevated. Most systems are raised and lowered by a hand- or foot-operated cable winch, although power winches are available for the taller scaffolds. Adjustable scaffolds using a winch are not as fast or easy to adjust as mast climbing work platforms. However, they are less expensive and offer many of the same advantages. It is best to buy a system with a winch that is easy to operate. Otherwise, laborers may not raise the platform often enough to keep work at waist height. Scaffolds are available in a variety of sizes to accomodate small residential jobs and large high-rise buildings. The two side by side images show an aerial view of scaffolds, while the third photo provides a close-up of work on a scaffold. More Detail An adjustable split-level scaffold allows a brick or block mason to stoop less because the materials and work surface are both kept near waist height, which is more comfortable and stresses your body less. Adjustable split-level scaffolds are available for jobs ranging from small single-story residential work to large high-rise building projects. This equipment may not be appropriate for all jobs. Less Detail
	Risks Addressed:	Musculoskeletal disorders due to overhead work, manual materials handling, stooped postures, and kneeling/squatting Injuries due to falls and falling objects
	How Risks are Reduced:	There are several ways that adjustable height scaffolding reduces the risk of developing painful conditions in the muscles and joints. First, compared to traditional scaffolding, the adjustable scaffold allows the work platform to be easily raised or lowered, keeping work between knee and shoulder height. A materials platform can be established at waist height. Working at waist level reduces bricklayer fatigue, and reduces the risk of back and shoulder problems associated with bending at low courses and reaching for courses above the chest. Second, the platform may be moved vertically with the work, because the work materials do not need to be moved each time the work platform is raised. This reduces the risk of developing work-related low back pain by decreasing heavy lifting and manual material handling at work, and reduces the risk of injury from falling objects. Third, unlike frame scaffolding, which requires constant building above the work area, adjustable tower scaffolding is assembled on the ground. This eliminates overhead work and awkward postures and reduces the risk of being struck by falling objects. Fourth, adjustable tower scaffolding is set up once and positioned with a forklift or crane, depending on wall configurations. There is no need for laborers to repeatedly build or tear down frames or manually handle planks. Lastly, adjustable scaffolds have integral guardrails, toe boards, braking systems, and fall arrest systems to ensure jobsite safety. Quality of Evidence Manufacturers, vendors, or worksites have reported a risk reduction. Safety and health experts believe there is a risk reduction. Research has shown that workers who spend more time working in a stooped posture or other awkward back postures are at a higher risk for developing low back problems. Studies have reported a decrease in low back pain and stress among those working with materials kept at or near waist height. Manufacturers also report that the ability to set the scaffold to any height allows workers to arrange materials between knee and shoulder height. Materials do not have to be moved as frequently, so there is less manual material handling of supplies and scaffolding parts. Research has shown that reduced manual materials handling decreases low back pain. There have not been independent published studies measuring the effect of using adjustable height scaffolding on the incidence of musculoskeletal disorders. Regardless, health and safety experts are convinced that worksites that use adjustable height scaffolding may have fewer incidents of musculoskeletal disorders among their workers due to reduced exposure to known risk factors.
	Effects on Productivity:	Adjustable tower scaffolding significantly increases worker productivity when compared to traditional tubular frame scaffolding. Gains in productivity result from decreased installation and dismantling time and improved mason productivity. The platform can be easily lowered to the ground for restocking, thus reducing or eliminating the cost of using heavy equipment to deliver materials to high levels of scaffolding. Quality of Evidence Independent published studies have found an increase in productivity. Manufacturers or vendors have reported an increase in productivity. An independent study conducted by the University of Texas showed that tower scaffolding increased mason productivity by more than 20%. Contractors agree, and some report 20-35% in productivity gains, depending on the type of wall. Health and safety experts believe reducing the risk of developing musculoskeletal disorders may lead to increased productivity because: 1) workers can use work for longer periods with less breaks and less fatigue, and 2) there may be a reduction in lost time injuries.
	Return on Investment:	No specific calculation ROI information exists for this particular solution, however, there are some general approaches that might be useful for a “Return On Investment” analysis. For a general discussion of these approaches, visit our “Return on Investment Calculation” page.
	Availability:	Where to Get It Non-Stop Scaffolding, Shreveport, LA Non-Stop Scaffolding CrankUp Scaffolding LLC, Atlanta, GA CrankUp Scaffolding U.S.A Hydro Mobile, L'Assomption, Quebec, Canada Hydro Mobile Approximate Cost Costs vary depending upon how the work platform is raised (manual vs. powered), the height of the masonry wall, and the overall size of the project. Heavy-duty scaffolding for three-story commercial work runs about $300 per lineal foot. Light-duty scaffolding for residential and light commercial work of the same height runs about $200 per lineal foot. Contractors who have used these systems say that productivity increases allow them to recover the cost, but actual benefits will vary.
	Additional Considerations:	Some contractors have reported more sprained wrists among laborers when using adjustable scaffolding compared to mast climbing scaffolding or traditional tubular scaffolding. Adjustable scaffolding with foot operated pum jacks may be better.
	Sources:	This solution is also referenced in: Albers, James T., and Estill, Cheryl F.. Simple Solutions: Ergonomics for Construction Workers. DHHS(NIOSH) Pub. No. 2007-. http://www.cdc.gov/niosh To view other solutions in this document go to http://www.cpwr.com/simple.html. Please send requests for copies of this publication to cdcinfo@cdc.gov reference number 2007-122.