Civil Engineering Reference
In-Depth Information
They illustrate three types of interventions, all of which were costed by the use of cost-benefit
analysis.
The ergonomics interventions (cases) are:
Section 4.4.1 — almost no-cost changes to the work methods where the management and men
experimented to find the best solution
.
Section 4.4.2 — an ergonomics intervention where an ergonomist altered working heights to over-
come poor posture
.
Section 4.4.3 — large capital investment where engineers designed new equipment for injury
prevention
.
We intend that these case studies are illustrative of cost-benefit analysis rather than ergonomics solutions
and are simplified examples of the ones given by Oxenburgh et al. (2004). For a more detailed analysis,
please see this reference.
4.4.1 Warehouse Work — Truck Loading
The manager of a warehousing and transporting enterprise became concerned when a number of his
warehouse staff and drivers began reporting of neck and shoulder pain. A risk assessment identified
the source of the shoulder and neck pains as arising from loading bulky packages into the delivery trucks.
The packages were about 1.5 m wide by 0.4 m in diameter, weighing about 8 to 10 kg, soft and flexible
and covered by a slippery plastic and, with no handles, the packages were awkward to handle. Although the
weight of the individual packages was not high their soft, flexible character made the packages awkward to
lift and, as the rows filled, it required pressure to push the last packages into position on each row.
The simple ergonomics solution was to provide a platform within the truck, which enabled the ware-
house staff to work at a height that gave them better mechanical efficiency. This eliminated most of the
loading above head height so that the top layers could be packed with minimal stress to the shoulders.
The warehouse staff have found the method more comfortable and they are not getting neck and
shoulder pains any longer.
Although the new packing system has been successful interms of injury prevention, has it been success-
ful in terms of cost-benefit analysis?
The new system increased the time required to load each truck from 35 to 45 min thus increasing the
cost to load each truck by about 30%. However, using the original loading system each truck was packed
to 89% volume capacity but, with the new system, the capacity was increased to 95%. This made such a
difference that the drivers were able to load the entire day's deliveries of product into one less truck.
Table 4.1 shows the cost-benefit analysis of the improved loading system. In this analysis only the direct
wage costs and truck running costs are used. Despite the increased loading
employment costs, the
improved loading of the trucks led to a net savings of about 45,000 “units” per year. The pay-back
period was less than 1 week.
/
TABLE 4.1 Cost-Benefit Analysis for Loading and Delivering Bulk Packages
Initial Case
Improved Loading
year)
a
Employment costs for the loading work (units
50,200
55,700
/
Truck costs (units
year)
501,400
451,300
/
Total yearly costs for loading and delivery
551,600
507,000
Intervention costs: management and warehouse staff
time (units)
b
—
625
Savings (units
year)
—
44,600
/
Pay-back period
—
1 week
a
For reasons of confidentiality, “units” are used for costing.
b
A “one-off ” cost.
Search WWH ::
Custom Search