Conventional Material Handling Methods: Manpower

Manpower refers to one or more employees physically pushing or pulling a load to its intended destination. This method of material mobility presents numerous safety hazards to workers, including overexertion and musculoskeletal disorders (MSDs). With manpower, the majority of the force required to build enough momentum to propel the load forward is through the initial exertion. Therefore, most injuries occur while workers are attempting to set a load in motion. Liberty Mutual Research Institute states that in 2009, the primary cause of serious workplace injuries arose from overexertion due to lifting, lowering, pushing, pulling, holding or carrying heavy loads—accounting for 24.5% of all work-related injuries and costing companies nearly $13 billion in direct costs each year.

Relying on manpower to move loads that weigh hundreds or even thousands of pounds contribute to the prevalence of musculoskeletal disorders within material handling applications. These disorders make up as much as one third of all work-related injuries and effect nearly all tissues, including the nerves and tendon sheaths. The physical strain required when using manpower often causes sprains, nerve damage, hernias and joint dislocations.

To help instill safer material handling procedures, the National Institute for Occupational Safety and Health (NIOSH) outlined parameters on what constitutes a material handling safety hazard. When deciding if a hazard exists, they consider the repetitiveness of lifting the distance from the load to the spine; the weight, size and stability of the load lifted; and the footing at the worksite. Though NIOSH provides helpful guidelines to avoiding injury when moving large or heavy loads, on a busy plant floor, operators do not always have the time to carefully calculate these factors before proceeding.