Ergonomics is the science and practice of designing jobs and workplaces to match the capabilities and limitations of the human body or, more simply, fitting the job to the worker.
According to the U.S. Bureau of Labor Statistics (BLS), in 2015, musculo-skeletal disorders (MSDs) accounted for 31 percent of total injury and illness cases for all workers. Work-related MSDs are among the most frequently reported causes of lost or restricted work time cases. These injuries occur gradually and involve muscles, tendons, ligaments, blood vessels, and joints of the neck, shoulders, arms, wrists, legs and back, which are often referred to as soft tissue injuries.
Ergonomics may be used in all workplaces to prevent MSDs. Workers will experience improved quality of work, improved quality of life, and reduced fatigue and discomfort.
In order to apply ergonomic practices in your workplace, let’s review some basic principles:
Identify Workers with Risk Factors
Evaluate workers performing custodial/janitorial, maintenance/service, and administrative activities to identify those with the common risk factors:
- Exerting force to perform a task or to use a tool (e.g., lifting tables/chairs or scrubbing with a brush).
- Working in awkward postures (e.g., bending or twisting the back, overhead reaching for dusting or painting, or mopping with elbows away from the body).
- Remaining in the same position for a long time with little or no movement (e.g., sitting at desk).
- Continuous pressure from a hard surface or edge on any part of the body (e.g., improperly adjusted chair and desk height).
- Working in hot or cold temperatures.
- Holding equipment that vibrates (e.g., the handle of a pressure washer).
If risk factors are present, then they need to be assessed to determine the significance of the risk.
Assess Significance of Risk Factors
Assess each risk factor to determine if they are likely hazards for MSDs by considering the following three things:
- Duration (how long) – Usually, duration involves hours of exposure and not just minutes. But, exposure can be cumulative over the day and not just all at one time.
- Frequency (how often) – Frequency addresses the speed of the work. Lifting
30 lb boxes more than 5 times per minute can be considered frequent.
- Intensity (how much) – Refers to force, such as weight in pounds lifted/carried, grip or pinch force, vibration level, and force on keys when typing.
The longer exposure to risk factors and a combination of risk factors will greatly increase the chance for injury. Symptoms such as discomfort, pain, numbness, tingling/burning, swelling/inflammation, changes in skin color and loss of flexibility may likely indicate a MSD. If no changes are made, then symptoms may get worse and result in lost work days.
Methods of Preventing MSDs
These are common methods for controlling MSDs, and rank in their order of effectiveness with the first (i.e., engineering controls) being the most effective.
- Engineering controls (e.g., redesign work areas to eliminate reaching, bending, or other awkward postures and providing carts for transporting materials)
- Administrative controls (e.g., providing sufficient breaks, since adequate recovery time can reduce fatigue, and employee training on safe lifting)
- Safe work practices (e.g. stretching and safe lifting)
- Personal protective equipment (e.g., knee pads for kneeling and gloves to protect against cold, vibration and rough surfaces). Note: NIOSH recommends that employers do not rely on back belts to protect workers as studies have shown they are not effective in preventing back injuries.
For detailed information on methods of preventing MSDs in your workplace, see the resources provided below.
Should you require additional assistance with ergonomic assessments or training in your workplace, please contact Gary Smith, CRM, at (517) 338-3367 or firstname.lastname@example.org.
Working Safer and Easier for Janitors, Custodians and Housekeepers; published 2005 by the California Department of Industrial Relations at http://www.dir.ca.gov/dosh/dosh_publications/Janitors.pdf
A Clean Sweep: Safe Work Practices for Custodians; published June 2006 by WorkSafeBC at https://www.worksafebc.com/en/resources/health-safety/books-guides/a-clean-sweep?lang=en
Office Ergonomics Resources including setting up a workstations and self-assessment forms at SAIF Corporation: https://www.saif.com/safetyandhealth/topics/prevent-injuries/ergonomics.html
Ergonomics Resources from OSHA at https://www.osha.gov/SLTC/ergonomics/