Original publication: 2020 | Peer-reviewed journal article
Source authors: B. E. Keenan, K. Hallas, A. K. Drahota and S. L. Evans
About this research
Can floors in hospitals and care homes reduce the severity of fall injuries while remaining practical for staff moving beds and other equipment?
Shock-absorbing materials can reduce forces during an impact, but flooring that compresses under load may also increase the effort needed to push or pull equipment. This creates a design problem with potential consequences for both vulnerable patients and healthcare workers.
Collaborative research by Cardiff University, the University of Portsmouth and HSE investigated these two properties together.
How the research was conducted
The researchers evaluated fourteen flooring materials from five suppliers, representing conventional coverings and specialist foam- or rubber-based constructions. An additional overlay configuration was assessed for wheeled-equipment movement.
In one test, a mechanical apparatus with an anatomical femur model and simulated soft tissue measured peak impact forces in a sideways-fall scenario. In a separate test, an instrumented arrangement measured the horizontal force required to initiate movement of a castor loaded to approximately 748 N — corresponding to one wheel of a 300 kg four-wheeled bed and occupant.
Key findings
Impact attenuation varied substantially between flooring constructions.
Reduction in the measured peak hip-impact force ranged from approximately 0.7% to 25.2%. Standard 2 mm vinyl provided little attenuation; a specialist 23 mm rubber underlay gave the largest reduction in the test configuration assessed.
Wheeled-equipment resistance also varied substantially.
For example, the force to start the loaded castor moving was about 54.5 N on standard 2 mm vinyl, 44.1 N on a 7 mm rubber-backed vinyl floor and 60.2 N on the specialist 23 mm rubber underlay. The underlay with an additional conventional vinyl overlay required about 85.3 N in that test.
Better impact absorption did not necessarily mean more resistance to equipment.
Across the investigated materials, the researchers found no statistically significant direct relationship between impact-force attenuation and horizontal pulling force.
Floor thickness was not the whole story.
Material type, surface construction and the arrangement of layers also affected performance. This suggested that flooring might be designed to improve protection without automatically creating unacceptable resistance to equipment movement.
Interpreting the results
The findings are from controlled mechanical tests, not a trial measuring actual hip fractures. The highest attenuation was measured for a rubber underlay without a top-surface overlay; the version with conventional vinyl was separately measured for wheel movement, not impact attenuation.
The wheel measurements represented a simplified arrangement with a castor aligned in the direction of movement. Actual movement of beds and equipment can be more demanding, especially when castors need to swivel or equipment must be manoeuvred in confined areas.
Why it matters
Healthcare flooring must satisfy multiple requirements: appropriate slip resistance, hygienic cleaning, comfort, impact protection, durability and manageable forces for wheeled equipment. One number cannot describe every relevant aspect of safety.
The study gives useful evidence that designers should measure the relevant properties separately and seek constructive solutions rather than assume an unavoidable trade-off.
Original research
Keenan, B. E., Hallas, K., Drahota, A. K. and Evans, S. L. (2020). A comparison of floor surfaces for injury prevention in care settings: impact forces and horizontal pulling force required to move wheeled equipment. Osteoporosis International, 31, 2383–2394. DOI: 10.1007/s00198-020-05520-y.
Original source and further reading
Publisher / original publication