Break the Cycle
Get a Grip on Material Handling Problems
Preventing overexertion injuries is a major workplace safety
challenge. According to the Bureau of Labor Statistics (BLS),
more than one million workers will suffer a back injury over
the next year. These types of injuries are predicted to account
for one-fifth of all workplace injuries or illnesses and cost
billions of dollars in addition to the pain and suffering experienced by employees. The BLS identifies manual material handling (lifting, pushing, pulling, and carrying) as the principal
cause of these compensable work-related injuries. Researchers
also estimate that 60–86 percent of people with acute low back
problems will have a recurrence within a year, and that at least
36 percent will experience two or more recurrences of low back
problems during that time.
It is not uncommon for companies to experience persistent
MMH problems. Adopting an improvement strategy that uses a
define–measure–control approach can stop the cycle of these
debilitating disorders. The following case study of customer
sales and service representatives (CSSRs) working in uniform
and apparel services illustrates that you don’t have to break the
bank to address this problem.
BY JOSH KERST
The first step was to clearly define the work conditions that increased the likelihood of MMH injuries for service reps. A cross-functional team defined factors that could contribute to recurring
MMH problems and evaluated those assumptions against loss
data (injuries, work restrictions, etc.) and feedback about the
CSSRs’ daily tasks. This team also identified work conditions of
multiple clients in various industries and regions, as well as
products that represented the biggest challenges across the entire
Objective MMH assessment tools were used to quantify the risks.
These tools included the NIOSH Lifting Equation; lifting guidelines derived from NIOSH that calculate the recommended weight
limit (RWL) based on multiplying a load constant (51 lbs.) by
various multipliers; the Snook/Liberty Mutual push/pull/carry
High-Risk MMH Tasks
Manually lifting and carrying
overfilled garment/linen bags
Table 1. Examples of Critical CSSR Tasks and Priority Controls
for Pilot Test
Handling large items
Entering/exiting vehicle with
Modified garment/linen collec-
tion bag (handles, bag material)
Improved hand cart design
Improved vehicle features
(handles, floor coatings)
tables, which provide the female and male population percentages capable of performing MMH tasks without overexertion;
and an additional tool that considered guidelines for previously
injured workers. This tool resulted from a partnership between
the Ohio Bureau of Workers’ Compensation (BWC) and The Ohio
State University (OSU). Researchers from OSU worked with BWC
personnel and Ohio employers to test MMH limits for employees
with previous back injuries, and developed guidelines based on
these laboratory studies ( www.ohiobwc.com/employer/programs/
When these guidelines were applied to the CSSR lifting tasks,
the lifting limits for previously injured workers were 30-50 percent lower than those predicted by traditional assessments.
These baseline results influenced the type and magnitude of future workplace control interventions.
The team reviewed a list of proposed controls ranging from
low-cost items to recommendations that required more capital.
Based on control feasibility, expected acceptance by workers,
and potential for overall risk reduction, the team created a list
of recommendations (see Table 1), which were tested and piloted in three locations.
Improvements were piloted over a six-week period. Follow-up
analyses indicated that overall MMH risk was reduced up to 40
percent across the problematic tasks. CSSRs demonstrated excellent retention of skills taught in training and provided positive feedback on the new equipment. Many of the
improvements increased operational efficiency. The cost to implement each recommendation was typically under $150—far
less than the average direct cost for a back strain ($8,750) or a
back injury requiring surgery ($57,500). No repeat injuries have
been recorded, and the pilot project is slated to be implemented
system-wide over the next 18 months.
Plan the Work, Work the Plan
Systematically addressing recurring MMH problems requires
proper planning and carefully selected controls with tested interventions that are guided by an experienced team. The methods, assessment tools, and control measures described here help
confirm that any organization can get a handle on preventing
repeat injuries—they just have to plan the work, and then work
Josh Kerst is vice president and ergonomics engineer at Humantech in
Ann Arbor, Mich.