Construction work is one of the most common and lucrative fields of employment among trades people and labourers. It has been well established that work in this field is associated with ergonomic risk factors and musculoskeletal disorders, and evaluating exposures to various risk factors throughout this work is important.

Although, accurate assessment of exposures can be difficult to gather without proper expertise and skills.

In an article by Tak et al. (2011), they use the PATH tool (Posture, Activities, Tools, Handling) to evaluate exposures to ergonomic risk factors at a highway construction site. They applied the tool by recording posture at various joints, activities performed, tools used and handling operations at 45-60 second intervals over 4 hour periods, across several days. After compiling the data, the various recorded items are tabulated to attain a percentage of exposure to various postures, activities, tools and handling risk factors.

Some highlights of the results of the observations are:

  • Most operations require a high frequency of trunk flexion. However, the Concrete Form Building, Concrete Reinforcement, Plastering, Grouting, and Tiling operations required non-neutral trunk postures for more than 40% of the work time, and these operations had a high amount of flexed and twisted posture. The job classification of general labourer had the least amount of exposure to trunk posture risk factors.
  • For upper limb exposures it was noted that Tiling, Plastering, Grouting and Pipejacking were most likely to have flexed armed postures at or above shoulder height.
  • Plasterers handled loads of 5-14.9 lbs for 54% of the time. Loads of 15-50 lbs were handled frequently in Concrete Form Building (11%) and Pipe Jacking (23%). Loads exceeding 50 lbs were observed most frequently for ironworkers (5%) and during Concrete Reinforcement (4%).

The authors note that this study can be used to target operations within jobs that are hazardous and require priority intervention. They cite the concrete pouring as an example. They report that although some previous studies have evaluated exposures in construction work, the strength of this study is that it relied on a quantitative tool, evaluated many different trade classifications, and used many different observations periods. This should give a more realistic representation of which job, and operations within each job, are most risky.

EWI Works comments:

This type of research highlights methods to capture work exposures. However, applying the tools and interpreting the results with proper statistical evaluation requires proper skill and training. With better knowledge of exposures, we can begin to develop targeted interventions to reduce injury risk in construction-related work. In addition, we can use this type of information to understand variability in exposures between operations/jobs, and use this to better design work to promote good job rotation and micro break strategies.


Tak, S; Buchholz, B; Punnett, L, et al. (2011). Physical ergonomic hazards in highway tunnel construction: Overview from the Construction Occupational Health Program. Applied Ergonomics, 42(5), 665-671.