Using half-weight cement bags is an administrative control that can reduce musculoskeletal disorders (MSD) from manual material handling and stooped postures.  A regular cement bag weighs approximately 94 pounds, which exceeds the NIOSH recommended lifting weight of 51 pounds. Half-weight cement bags fall withing NIOSH recommendations.

 

Mason tenders work in support of bricklayers and blocklayers. A regular part of their work involves carrying or lifting heavy cement bags (94 lbs) and manually emptying them into mortar mixers. The weight of these bags (94 lbs and up) exceeds the NIOSH recommended lifting weight of 51 lbs.  Decreasing the weight, by using half-weight cement bags, significantly reduces the risk of low back pain and back injury. 

With the use of half-weight cement bags, mason tenders would  probably have to lift twice as many bags.  However, lifting half-weight cement bags is less fatiguing and should not slow down productivity.

Research in exercise physiology has shown that lifting a weight near a person's maximum lift capability is much more exhausting then lifting even a slightly reduced weight.  Exercisers can be expected to perform 12 lift repetitions with a weight that is about 70% of their maximum lift weight. Maximum productivity is likely to be achieved at even lower percentages of maximum lift weight.  Productivity gains begin at the point where increase in repetion rate plus reduction in recovery time (both immediate and long term) exceeds time lost to multiple repetitions.  

Dan Anton, PT, PhD, ATC – Eastern Washington University, and Carlos Sanchez-Marin, DDS, MS – University of Iowa

• Masonry, Tile, Cement & Plaster
  • Mix cement, mortar, plaster, or grout
    • Lifting and Carrying (Manual materials Handling)