2.1. Sample
Data was collected from a sample of 224 workstations involving
567 tasks located in 18 plants from various industrial sectors: one
appliance manufacturer, four plastics and composites manufacturers,
six public-sector tree nurseries, five food processing plants,
one aerospace manufacturer and one manufacturer of musical
instruments (see Table 1). Given the small number of workstations
in the food, aerospace and musical instrument plants, these sectors
are shown as a single group (Other) to simplify the presentation of
the results. The workstations were chosen (a) because they were
targeted by CSST (Quebec’s Workers’ Compensation Board)
inspectors as having a history of MSDs, (b) directly by the company
itself following workers’ complaints or (c) by the company as
workstations at risk for causing MSDs that were also in need of
changes to increase productivity. In all cases, workstations were
judged to be causes of concern for MSDs. For this study, assessments
were performed on workstations with cycle times ranging
from 0.03 min to 18.75 h (see Table 1). As such, the methods were
compared using a sample with a wide variety of cycle times. The
tree nursery and appliances sector workstations had the shortest
cycle times (average 1.1 and 0.8 min), while those from the aerospace
and plastics/composites manufacturing sectors had the
longest (average 90.7e450.0 min). Where workstations were used
by more than one worker, measurements were taken for more
than one worker. Since workstations in the tree nursery sector
are seasonal, some workers occupied more than one workstation
over the course of the data collection. They were therefore
observed and questioned at more than one workstation.