Abstract
Pallet jacks used in manual material handling jobs are commonly pulled behind the operator to allow full visibility, resulting in awkward shoulder extension and trunk rotation. In this laboratory study, we compared an alternative handle with a standard handle during use when traveling with the pallet jack behind the operator. Total oxygen consumption, usability, comfort, and preference were compared between the two handles. The results showed different advantages associated with each handle design, leading to the conclusion that a secondary handle, used in conjunction with a primary standard handle, may be a beneficial intervention for pallet jack use.
References
| Al-Eisawi K. W., Kerk C. J., Congelton J. J., Amendola A. A., Jenkins O. C., Gaines W. (1999). Factors affecting minimum push and pull forces of manual carts. Applied Ergonomics, 30, 235–245. Google Scholar Medline | |
| Borg G. (1998). Borg’s Perceived Exertion and Pain Scales. Champaign, IL: Human Kinetics. Google Scholar | |
| Bureau of Labor Statistics. (2009). Survey of occupational injuries and illnesses in cooperation with participating state agencies. Retrieved from http://www.bls.gov/iif/oshwc/osh/case/ostb1968.pdf Google Scholar | |
| Caldwell L. S., Chaffin D. B., Dukes-Dobos F. N., Kroemer K. H. E., Laubach L. L., Snook S. H., Wasserman D. E. (1974). A proposed standard procedure for static muscle strength testing. American Industrial Hygiene Association Journal, 35, 201–206. Google Scholar Medline | |
| Hoozemans M. J., Kuijer P. P., Kingma I., van Dieën J. H., de Vries W. H., van der Woude L. H., Veeger D. J., van der Beek A. J., Frings-Dresen M. H. (2004). Mechanical loading of the low back and shoulders during pushing and pulling activities. Ergonomics, 47, 1–18. Google Scholar | |
| Hoozemans M. J., van der Beek A. J., Frings-Dresen M. H., van der Woude L. H., van Dijk F. J. (2002a). Low-back and shoulder complaints among workers with pushing and pulling tasks. Scandinavian Journal of Work, Environment and Health, 28, 293–303. Google Scholar | |
| Hoozemans M. J., van der Beek A. J., Frings-Dresen M. H., van der Woude L. H., van Dijk F. J. (2002b). Pushing and pulling in association with low back an shoulder complaints. Occupational and Environmental Medicine, 59, 696–702. Google Scholar | |
| Hoozemans M. J., van der Beek A. J., Frings-Dresen M. H., van Dijk F. J., van der Woude L. H. (1998). Pushing and pulling in relation to musculoskeletal disorders: A review of risk factors. Ergonomics, 41, 757–781. Google Scholar | |
| Kumar S. (1994). The back compressive forces during maximal push-pull activities in the sagittal plane. Journal of Human Ergology, 23, 133–150. Google Scholar | |
| Lee K. S., Chaffin D. B., Herrin G. D., Waikar A. M. (1991). Effect of handle height on lower-back loading in cart pushing and pulling. Applied Ergonomics, 22, 117–123. Google Scholar | |
| Plouvier S., Renahy E., Chastang J. F., Bonenfant S., Leclerc A. (2008). Biomechanical strains and low back disorders: Quantifying the effects of the number of years of exposure on various types of pain. Occupational and Environmental Medicine, 65, 268–274. Google Scholar |
Carisa Harris-Adamson received her PhD in environmental health sciences from the University of California, Berkeley (UC Berkeley), in December 2010 and her master of science in physical therapy from the University of California, San Francisco, in 2001. She is an assistant professor in the Department of Physical Therapy at Samuel Merritt University, and is doing a postdoc at UC Berkeley.
Jia-Hua Lin has been a member of the Liberty Mutual Research Institute for Safety staff since 2001. Previously, he has worked as a teaching and research assistant at the University of Wisconsin–Madison. A member of the Human Factors and Ergonomics Society, Lin graduated from the University of Wisconsin–Madison with an MS and PhD in industrial engineering.
