Specific Guidance 2.2: Medical Chairs
Overview
This specific guidance addresses medical chairs, which were identified in the RERC-AMI's national consumer survey (Winters et al., 2007) and through focus groups (Story et al., 2005) as key pieces of equipment causing access barriers to healthcare services. Medical chairs include chairs used for a wide variety of examinations and procedures. The specific guidance provided here is based on existing legislation (Americans with Disabilities Act Accessibility Guidelines, ADAAG) and expertise and experience of RERC-AMI staff.
2.2.1 The height of the chair should be adjustable.
Discussion: The table should adjust in height to suit the needs and preferences of patients with different needs and preferences, as well as the needs of medical professionals of different heights and as appropriate for specific procedures.
The preferred minimum height is 17 inches (ADAAG), although this is not currently available for all types of medical chairs. The 17-inch height makes it possible for some wheelchair users to transfer themselves onto the chair from the wheelchair, and for some people of short stature to use the chair independently.
However, wheelchair users and some ambulatory people may prefer to have the chair at a higher height (e.g., 19 or 20 inches) when getting off the chair. It is easier for wheelchair users to transfer themselves from a chair that is higher than the seat of the wheelchair (so they are working with the force of gravity rather than against it), and it is easier for individuals with weaker quadracep (thigh) muscles to stand up from a higher seat (Demura & Yamada, 2007).
2.2.2 The weight lifting capacity of height-adjustable chairs should be at least 300 lb.
Discussion: A 300-lb. capacity to lift patients while they are on the table will accommodate at least 99% of the U.S. population.
In 2003-2004, the CDC’s National Health and Nutrition Examination Surveys (NHANES) found that 32.2% of Americans age 20 and older (31.1% of men and 33.2% of women) were obese (BMI ≥ 30.0). For a 6-foot-tall person, this would be a weight of more than 221 lbs. In addition, 2% of Americans were morbidly obese (BMI ≥ 40.0). For a 6-foot-tall person, this would be a weight of more than 295 lbs. (NCHS, 2006). Medical facilities should be prepared, however, to accommodate people who weigh much more than 300 pounds, possibly with a bariatric gurney.
2.2.3 Controls for chair adjustments (e.g., height, back angle) should be located appropriately for the application.
Discussion: For some chair uses, it is appropriate to allow patients to adjust the chair themselves to suit their personal needs and preferences. For other uses, only medical personnel should adjust the equipment. For example, when patients may be left alone in the chair for some period of time, it would be desirable for them to be able to adjust the chair so they could shift their body positions, particularly to avoid pressure sores.
2.2.4 The stiffness of the chair padding or cushion should be appropriate to the application.
Discussion: Softer surfaces are more comfortable and appropriate for chairs on which patients must remain for a substantial period of time; however, they can more more difficult to transfer on and off, especially for wheelchair users and others who perform lateral transfers. In contrast, firmer surfaces are less comfortable but can be easier to transfer onto and may be appropriate for applications in which patients remain on the surface for only a short duration. More research is needed to investigate the optimal characteristics of transfer surfaces.
2.2.5 The chair should have handholds to improve patient safety and enhance independence while getting on or off the equipment.
Discussion: Handholds on chairs may be side rails, arm rests, grab bars, vertical poles, or other elements that provide a secure grip for patients while maneuvering their bodies relative to the chair. Patients may use handholds while getting on or off the equipment, or while repositioning themselves while on it.
2.2.6 The chair should have side rails or armrests available. The side rails should drop down or be removable so they will not obstruct patient transfer or hinder professional diagnosis or treatment.
Discussion: Side rails or armrests enhance patient comfort, safety and security while sitting on the chair or while repostioning themselves. However, they may need to move out of the way when patients are getting on and off, depending on individual patient needs and preferences. They may also need to be removed to increase healthcare professionals’ physical access to the patient. The table should provide a place to store the side rails in or on the table (e.g., in a side recess or in a drawer on the back or hanging on a wall nearby) so they will be readily available when needed.
2.2.7 The chair cushion should be wide enough to allow the patient to manuever safely and comfortably into any body position that may be needed or desired (e.g., shift pressure points).
Discussion: The maximum current standard chair width is 24 inches for fixed-height chairs and 21 inches for adjustable-height chairs, but wider widths make it easier for patients to position or reposition their bodies on the chair. For medical facilities that serve bariatric (obese) patients, wider chairs would be prefereable.
2.2.8 Any leg and/or foot supports and/or headrests on the chair should be adjustable and lockable.
Discussion: Some patients have asymmetric bodies or have limited ranges of motion or prefer different body positions, and this feature would enable them to assume and maintain a variety of positions, as may be required for specific medical procedures.
2.2.9 Any wheels on chairs should be lockable.
Discussion: To enhance patient stability and safety, chairs must be stable while patients transfer on and off.
2.2.10 The base of the chair should not extend past the edge of the patient support surface or cushion.
Discussion: A base that extends past the edge of the chair may prevent patients who use wheelchairs from maneuvering close prior to transferring, which may make the process less safe. The edge of any flat plate where the chair base meets the floor should be beveled or sloped so it will not be a tripping hazard or rolling obstruction. More research is needed to understand the base clearance needs of wheelchair users, including the needs of people who transfer laterally and those who transfer forward.
2.2.11The chair should provide clearance for lift equipment.
Discussion: The base of the chair may be narrow enough for portable lift equipment to straddle the end of the device, or it may have clear space underneath the body of the chair to accommodate the legs of portable lift equipment. The chair should have a clear path of travel for overhead lift equipment, if applicable.
Training
2.2.12 For ambulatory patients, height-adjustable chairs should be set to the height of the patient’s mid-thigh for getting on and off.
Discussion: People with weak quadracep (thigh) muscles find it easier to sit down and sit up from a seat that is taller than a typical chair (17-19 inches) (Demura & Yamada, 2007).
2.2.13 Positioning aids should be offered to patients.
Discussion: A variety of auxiliary support devices should be offered to support and stabilize patients to maintain comfortably specific positions of their bodies, arms, legs, head, or other body parts, as needed. The auxiliary devices may be foam wedges, shaped cushions, pillows, and/or straps (e.g., woven material with velcro closures).
References
Demura, S. & Yamada, T. (2007) Height of chair seat and movement characteristics in sit-to-stand by young and elderly adults. Percept Mot Skills, 104(1):21-31.
National Center for Health Statistics (2006). Prevalence of overweight and obesity among adults: United States, 2003-2004. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention.
Story, M.F., (2005). Focus groups on accessibility of medical instrumentation. In Proc. RESNA 2005 Ann Conf. 2005: Atlanta, GA.
Winters, J.M.W., et al. (2007). Results of a national survey on accessibility of medical instrumentation for consumers. In Medical Instrumentation: Accessibility and Usability Considerations, J.M. Winters and M.F. Story, Eds. Boca Raton: CRC Press, 13-28.