1) Reducing musculoskeletal stresses. If a contractor is not required by law to address these stresses in workers, explain whether it is cost effective to take active steps to reduce these stresses. Provide examples of the basic steps that can be taken.

2) Overtime hours and productivity: (Refer to table 13.8, page 391)

A contractor is required to finish a project at the end of four weeks. She works a crew of 5 workers (Crew A) for all four weeks on a 50 hour week. This schedule is able to finish the project on time. Workers earn $20 per hour for the first 8 hour per day, or 40 hours per week. For the extra hours above the 40 hour week, each worker earns 1.5 times the regular rate. (Hint: Table 13.8 uses the 40-hour work week as a reference standard - workers can continue indefinitely at a constant productivity level. The 50 - hour week is shown in comparison.) a. Determine the number of hours actually worked.

b. Calculate the cost of labor for this alternative

c. Determine the effective labor hours at standard productivity. From the table use the productivity rate for weeks 1 and 2, then for weeks 3 and 4.

d. Calculate the size of the crew required to a standard 40 hour week over the same 4-week period (Crew B - Use whole numbers for the weeks- crew size can be fractional)

Managing the Impacts of Scheduled Overtime on Productivity The Business Roundtable (BRT) conducted a study in 1974 on the impact of scheduled overtime operation on construction projects with respect to worker productivity and labor costs. The BRT repeated the study in 1980 and obtained similar results. The BRT study identified disproportionate increases in project costs to accomplish construction work when it was done with scheduled overtime, as compared with a nominal 40-hour week. This premium became larger as overtime was continued for several weeks; the BRT found that a schedule of 60 or more hours per week would potentially delay a project if it were continued for more than two months with the same crew size. Table 13.8 shows raising scheduled hours from 40 to 50 results in lower productivity for the entire 50-hour period. More recent studies by other researchers obtained similar results to the BRT's findings. Thomas et al. (1997) observed losses of efficiency of 10-15% for 50- and 60-hour work weeks. For this analysis, disruptions in three categories-resource deficiencies, rework, and management deficiencies-were analyzed. The analyses showed that the disruption frequency, which is the number of disruptions per 100 work hours, worsened as more days per week were worked. This led to the conclusion that losses of efficiency are caused by the inability to provide materials, tools, equipment, and information. Hanna et al. (2005) observed behaviors similar to those identified in the BRT study. Mayo et al. (2001) included TABLE 13.8 Relationship of Hours Worked to Productivity 1 2 5 7 50-Hour Productivity Actual Hour Hour Hour Loss Hour Cost Overtime Rate Output for Gain Over Due to of Overtime Work 40-Hour 50-Hour 50-Hour 40-Hour Productivity Premium Operation Weeks Week Week Week Week Drop Hours (at 2x) 0-1-2 1.0 926 46.3 6.3 3.7 10.0 13.7 2-3-4 .90 45.0 5.0 5.0 10.0 15.0 4-5-6 .87 43.5 3.5 6.5 10.0 16.5 6-7-8 8 40.0 0.0 10.0 10.0 20.0 8-9-10 .752 37.6 -2.4 12.4 10.0 22.4 $10 .75 37.5 -2.5 12.5 10.0 22.5