Case Types -Construction Site Injury Claim

Musculoskeletal Injuries in the Masonry Trade

Masonry Trade includes: Construction concrete workers, bricklayers, Stone, brick, concrete, hollow-tile, concrete block, gypsum block, or other similar building units or materials or a combination of the same, bonded together with mortar to form a wall, pier, buttress, or similar mass.

High-risk Factors

In the masonry trade, conditions that carry a high risk of work-related musculoskeletal injuries were identified through site observations and ergonomic analysis.

• Workers often perform more than 1000 forward bending tasks per shift and are therefore at risk of developing low-back disorders.
  
• Workers who have to lay brick and block above shoulder height increase their risk of developing shoulder, arm, and wrist problems.
  
• Masonry workers are exposed to environmental factors such as wind and excessive heat and cold. Walking or working on uneven, muddy, or icy surfaces exposes bricklayers and mason tenders to the risk of slips, trips, and falls.
  
• Workers generally use large trowels (12-inch) that enable them to lay more mortar per application but also increase the risk of elbow and wrist injuries.
  
• Many workers wear gloves when lifting and placing block. Gloves actually reduce grip strength.
  
• Mortarboards are typically positioned at or below knee level. This forces workers to bend forward repetitively -- a contributing factor to low-back disorders.
  
• Bricklayers often work in restricted spaces where their freedom of movement is limited. As a result they must adopt awkward, twisting movements when lifting and laying brick and block. This increases the risk of musculoskeletal injury.
  
• The stress of maintaining the expected production rate (about 200 blocks or 600 bricks per day) can lead to muscle tension and greater likelihood of injury.
  

Working against gravity in this awkward posture creates high musculoskeletal loads and reduces blood flow to muscle and other tissue. The posture requires that the muscles of the upper shoulder and back lengthen while they also contract. At the same time, forearm and hand muscles must be held in a contracted position to maintain grip on the block while it is being carefully lowered. All of this muscle activity in an awkward posture requires high energy expenditure and causes fatigue.

Disclaimer for above content : This document was published in 1993 as OSHA Fact Sheet No. 93-03. This is one of a series of fact sheets highlighting U.S. Department of Labor programs. It is intended as a general description only and does not carry the force of legal opinion.

See in full at : http://www.cdc.gov/elcosh/docs/d0100/d000142/d000142.html