Architectural and Transportation Barriers Compliance Board

Standards for Accessible Medical Diagnostic Equipment

Transfer Examples

Video:  30 second video showing a woman transferring from her wheelchair to an exam table with no assistance, a woman transfer from an exam table to her wheelchair with minimal assistance and a young man being transferred from his wheelchair to an exam table.

 Photographic still from video clip.

Transfer Surface Size

 Illustration of an exam chair with the transfer surface highlighted showing 21 inches wide minumim and 15 inches deep minimum.
M302.2.2 Size
Illustration of an exam table with the transfer surface highlighted showing 30 inches wide minimum and 15 inches deep minimum.
M301.2.2 Size
Two distinct requirements for each equipment category – difference as proposed is width

M301 Diagnostic Equipment Used by Patients in Supine, Prone, or Side-Lying Position
Photograph of the Access Board Executive Director and Board Members looking at imaging equipment. Photograph of an exam table
May not have back support.

ANSI/AAMI HE75

16.4.7 Contact surfaces

e) The support surface should be wide enough to enhance patient safety and comfort.

“For platforms on which patients lie down, patients should be able to roll to a side or prone position with minimal need to lift and shift their center of gravity.  For example, a standard exam table is approximately 27 inches wide and a bariatric table is approximately 30 to 32 inches wide, but a wider surface makes repositioning easier to accomplish.”

Picture showing the cover of ANSI/AAMI HE75:2009 Human factors engineering design of medical devices document.

30'' wide min. and 15'' deep min.

Width is based on comments by the Disability Rights Education and Defense Fund (DREDF) in response to DOJ’s ANPRM on equipment and furniture.

Generally consistent with the dimensions for rectangular seats in roll-in showers in the 2004 ADA and ABA Accessibility Guidelines.

 Illustration of the lower end of an exam table with the transfer surface highlighted showing 30 inches wide minimum and 15 inches deep minimum.

30'' wide min. and 15'' deep min.
Illustration 1 of 3 from the ADA/ABA Guidelines; figure 608.2.2 [Standard Roll-In Type Shower Compartment Size and Clearance], which depicts the standard roll-in type shower compartment with size and clearance measurements. Illustration 2 of 3 from the ADA/ABA Guidelines; figure 610.3 [Extent of Seat], (a) [rectangular], which depicts the 3 inch maximum distance allowed between the shower compartment entry and the shower seat. Illustration 3 of 3 from the ADA/ABA Guidelines; figure 610.3.1 [Rectangular Shower Seat], which depicts the required size and location of the rectangular shower within the shower compartment.
Seat sizes in widths of 26'', 28'' and 30'' for minimum size shower — 14.5'' and 15'' deep.

M302 Diagnostic Equipment Used by Patients in Seated Position
photograph of an exam chair with headrest, armrests and footrest. Illustration is of person transferring from wheelchair onto an exam chair.  This illustration is taken from the “Example Applications of the Proposed Medical Diagnostic Equipment Accessibility Standards” document.
Differences from “tables”.

21'' wide min. and 15'' deep min.

Width is based on the ideal chair width recommended in Architectural Graphic Standards for auditorium seating.

Depth is generally consistent with the dimension for rectangular seats in roll-in showers in the 2004 ADA and ABA Accessibility.

Illustration of an exam chair with the transfer surface highlighted showing 21 inches wide minumim and 15 inches deep minimum.

Transfer Surface Research

  • No research directly addresses
  • Do have sources of anthropometric data

Anthropometric Data

Concerns about 15'' min. depth:

The Measure of Man & Woman (Henry Dreyfuss Associates, 2002)

Seat Depth:
16 inches – all adults
20 inches max. – for lounge or leisure or tall adults

Illustration of Anthropometric data from Dreyfuss, The Measure of Man & Woman showing seat depth for different size adults.

Anthropometric Data

Concerns about 30'' min. width:

Distance required to reach supports

Reference to 50th percentile male from The Measure of Man & Woman (Henry Dreyfuss Associates)

Midmark [625 Exam Table w/ 32'' Wide Upholstery] illustration showing a 50 percentile male transferred onto an exam chair with a transfer surface of 30 inches wide and 15 inches deep.

Anthropometric Data

Concerns about 30'' min. width:

28'' minimum width proposed

Reference to 50th percentile female from The Measure of Man & Woman (Henry Dreyfuss Associates)

Midmark [623 Exam Table w/ 28'' Wide Upholstery] illustration showing a 50 percentile female transferred onto an exam chair with a transfer surface of 30 inches wide and 15 inches deep.  The 30 by 15 inch transfer surface is highlighted in purple with a 28 inch wide highlight superimposed over it.

Anthropometric Data

29'' min. width proposed
21'' seat width plus 8'' for 2 hands
The Rules of Work (Author Dan MacLeod, 2000)

95th Percentile Male:
Hand Breath – 3.9 inches
Hip Breath – 16.1 inches
16.1 + 2 × 3.9 = 23.9

Note differences from female

An illustration of a page taken from “The Rules of Work” by Author Dan MacLeod showing a table giving anthropometric data for male and female adults.

Anthropometric Data

The Measure of Man & Woman

95th Percentile Male:
Hip Sit – 16.9 inches

99th Percentile Male:
Hand Width – 4.6 inches

16.9 + 2 × 4.6 = 26.1

Illustration [99 PERCENTILE MAN] showing measurements for a 90 percentile man. Illustration [HAND DATA, MAN] shows measurements for the hand of a 90 percentile man.]

Anthropometric Data

Wheeled Mobility Anthropometry Project:

  • Anthropometric data on people who use mobility devices
  • Includes many relevant dimensions
  • More detailed presentation following

www.udeworld.com/anthropometrics

 An illustration of a page taken from the Wheeled Mobility Anthropometry Project showing clear floor space requirements.

Dimensions Analyzed

A:  Thigh breadth bi-lateral

B:  Bi-deltoid (Shoulder) breadth

C:  Posterior seat to popliteal length

D:  Seat depth

 Illustration showing both the forward and side views of a person seated in a wheelchair.
Illustration of a box-plot showing the distribution for thigh breadth stratified by gender and mobility device type.  The horizontal line splitting the box depicts the median, the box length represents the inter-quartile (25th – 75th percentile) range, and the whiskers represent the minimum and maximum values.  Extreme values are shown as dots and asterisks. The red dotted lines depict the observed range of 95th percentile values across sub-groups.
Illustration of a box-plot showing the distribution for shoulder breadth stratified by gender and mobility device type.  The horizontal line splitting the box depicts the median, the box length represents the inter-quartile (25th – 75th percentile) range, and the whiskers represent the minimum and maximum values.  Extreme values are shown as dots and asterisks. The red dotted lines depict the observed range of 95th percentile values across sub-groups.
Illustration of a box-plot showing the distribution for approximate buttock-popliteal length stratified by gender and mobility device type.  The horizontal line splitting the box depicts the median, the box length represents the inter-quartile (25th – 75th percentile) range, and the whiskers represent the minimum and maximum values.  Extreme values are shown as dots and asterisks.  The red dotted lines depict the observed range of 95th percentile values across sub-groups.
Box-plot showing the distribution for approximate wheelchair seat depth stratified by gender and mobility device type.  The horizontal line splitting the box depicts the median, the box length represents the inter-quartile (25th – 75th percentile) range, and the whiskers represent the minimum and maximum values.  Extreme values are shown as dots and asterisks.  The red dotted lines depict the observed range of 95th percentile values across sub-groups.

IDeA Center Memo Conclusions

  1. Proposed minimum width of 30 in. provides sufficient space for almost all individuals in sample based on static measurements.  Could be reduced to 28'' and still accommodate 95%.
  2. Width of 30'' would also accommodate the shoulder breadth of most individuals.  Reducing width to 28'' would still accommodate 95% of sample.
  3. Increasing minimum width is recommended for individuals that are morbidly obese and/or use bariatric wheelchairs if also a priority.  Reference maximum values recorded for thigh and shoulder breadth.
  4. Depth of 15'' for a seating surface found suitable based on median values of buttock-popliteal length and wheelchair seat depths.
  5. Results reflect static anthropometry measurements and are a starting point.  User testing is recommended for arriving at more accurate transfer surface dimensions and design.

Considerations

  • What Data sets to use?
  • What gender and percentile would be a good benchmark?
  • How much to extrapolate from “static” anthropometric dimensions?
  • Balance between the use of different equipment features?
  • Multiple recommendations?