Safe Patient Handling and Mobility (SPHM)

Man on his side on couch in rehabilitation center

Patient Handling Hazards

The Healthcare and Social Assistance sector (HCSA) has one of the highest rates of work-related injuries and illnesses and it continues to rise. In 2020, the Bureau of Labor Statistics (BLS) reported a 40% increase in injury and illness cases. HCSA had 806,200 private industry injury and illness cases in 2020 (2020 Survey of Occupational Injuries and Illnesses, BLS). Over half of these cases (447,890) resulted in at least one day away from work. The total incidence rate for this sector was 5.5 cases per 100 full-time equivalent workers in 2020, compared to 3.8 per 100 full-time equivalent workers in 2019. Nursing assistants experienced the highest rates of musculoskeletal disorders of all occupations in 2020, with 15,360 cases. Musculoskeletal disorders made up 52% of all days away from work cases for nursing assistants. BLS data collected in 2020 compared 10 medical occupations and found nursing assistants, registered nurses and licensed practical and licensed vocational nurses had notable increases in the number of days away from work.

The single greatest risk factor for overexertion injuries in healthcare workers is the manual lifting, moving, and repositioning of patients, residents, or clients, i.e., manual patient handling.

Patient Handling Ergonomics

Occupational safety and health programs have fostered research to identify injury risk factors and safety interventions to prevent injuries during patient handling. Evidence-based research has shown that safe patient handling interventions can significantly reduce overexertion injuries by replacing manual patient handling with safer methods guided by the principles of “Ergonomics.” Ergonomics refers to the design of work tasks to best suit the capabilities of workers. In the case of patient handling, it involves the use of mechanical equipment and safety procedures to lift and move patients so that health care workers can avoid using manual exertions and thereby reduce their risk of injury. At the same time, patient handling ergonomics seeks to maximize the safety and comfort of patients during handling.

Collaboration among partners in government, industry, and academia has provided a great deal of information on safe patient handling through publications, conferences, and safety training programs. To date, most of the research has focused on the handling of “average-sized” patients in institutional settings such as hospitals and nursing homes. Continued research in these and other settings such as home health care and emergency response, and with obese and morbidly obese (“bariatric”) patients is needed. The research-based evidence gathered thus far has led to the development of safe patient handling standards, and ongoing legislation to enact laws requiring or promoting the use of safe patient handling programs in health care settings.

Patient Handling and the Revised NIOSH Lifting Equation (RNLE)

One question that has been raised about patient handling is, “How much weight can be safely lifted without using assistive equipment?” When it comes to questions about lifting, many safety professionals rely on the Revised NIOSH lifting Equation (RNLE). This update of the RNLE manual corrects typographical errors in the previous version and is reformatted to be searchable and 508 compliant. NIOSH researchers developed the RNLE to determine weight limits for preventing back injuries caused by manually lifting objects on the job. Research studies have validated the equation’s usefulness for computing safe weight limits when lifting inanimate objects such as boxes and other packages. As a matter of policy, NIOSH recommends its use for that purpose.

The RNLE is not intended to be used for determining safe weight limits when lifting people. The shape and size of the human body differ from person to person, and patient handling situations are often complicated by many other factors such as the potential for unpredictable movements, the patient’s medical condition, and so on.  Since the equation was designed to be used for more stable and predictable lifting tasks, it is generally considered to be impractical for patient handling tasks.

As the field of safe patient handling grew over the years, practitioners increasingly expressed interest in trying to determine how much weight can be lifted safely using manual methods, and how much weight requires using lifting equipment. Dr. Thomas Waters examined the issue further and published an article entitled “When is it Safe to Manually Lift a Patient?”. The article describes how the RNLE “can be used to calculate a recommended weight limit for a limited range of patient-handling tasks in which the patient is cooperative and unlikely to move suddenly during the task.”

When lifting a box or other inanimate object, the lifter can usually get quite close to the object, which helps minimize strain caused by reaching while lifting. It is usually not possible to get as close when lifting a patient. In order to accommodate the added space needed when lifting a person, Dr. Waters increased the equation’s minimum horizontal distance of 10 inches (between the lifter’s spine and the object) to 14.5 inches (between the lifter’s spine and the patient). After including this change in the equation, he applied the RNLE and determined that under the assumption of an otherwise “ideal” patient handling situation, the maximum recommended weight limit is 35 lbs.

Based on Dr. Waters’ calculation, lifting algorithms developed by the Veterans’ Health Administration and the Association of periOperative Nurses state that assistive equipment should be used if the weight to be lifted by any single person exceeds 35 lbs. However, the guidance provided along with the algorithms advises that the 35 lb. limit is not, by itself, sufficiently protective under all circumstances. As explained below, assistive devices are still needed in most situations, even when the weight to be lifted is less than 35 lb.

“Limited Guidance” – Not “NIOSH Policy:” Caution regarding the 35 lb. Limit

When Dr. Waters derived 35 lb. as the maximum acceptable weight for manual patient handling, his calculation assumed the most ideal, low-risk situation for lifting a person. In his article, Dr. Waterst cautioned that even with cooperative patients, many conditions reduce the weight limit even further. These include “lifting with extended arms, lifting when near the floor, lifting when sitting or kneeling, lifting with the trunk twisted or the load off to the side of the body, lifting with one hand or in a restricted space, or lifting during a shift lasting longer than eight hours.” Most patient handling tasks occur under one or more of these circumstances, and certain physical/medical conditions can compromise the patient’s safety during manual handling. Clearly, the majority of patient handling situations are far less than ideal, thus NIOSH cannot designate 35lb, nor any other weight, as a protective “exposure limit” for patient handling. Instead, NIOSH shares in the consensus among patient handling professionals that the goal of safe patient handling programs should be to eliminate all manual lifting whenever possible.

National Safe Patient Handling Programs and Standards

Healthcare and Social Assistance (HCSA) is one of many occupational sectors studied by U.S. federal agencies such as the BLS, The Occupational Safety and Health Administration (OSHA), and the National Institute for Occupational Safety and Health (NIOSH). Guided by NORA-identified research priorities, the mission of the NIOSH HCSA research program is to eliminate occupational diseases, injuries, and fatalities among workers in this sector. Much of this research focuses on safe patient handling.

The Veterans Health Administration (VHA) provides resources for safe patient handling and mobility programs, implementations, patient care ergonomic assessments, and patient handling and mobility technology.

These resources include related to developing and maintaining safe patient handling programs.  They also include algorithms that can be used to maximize safety while handling and mobilizing all patients, with extra guidance specific to “patients of size,” i.e., “bariatric” patients.  Easy access to the algorithms and other tools is now available on a free mobile app.

Laws and Legislation

NIOSHTIC-2 is a searchable bibliographic database of occupational safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.

View search results on Safe Patient Handling

Upcoming Conferences

Safe Patient Handling and Mobility/Falls Conference Coming in 2023

SPHM Conference – TVAREF (

2023 ASPHP National SPHM Education Event

ASPHP Events