TABLE 1.
Findings from the International Organization for Standardization standard testing studies of manual wheelchairs.
| Author and year | Wheelchair samples | Test results and critical failures |
|---|---|---|
| ISO testing of manual wheelchairs (no data available on design type and manufacturers) | ||
| Cooper et al. (1994) | Nine manual wheelchairs | All wheelchairs failed on MDT. Failures observed with castor spindle, bearings and alignment. Bent cross braces were found. Splaying and toe-outs observed in rear wheels. |
| Rentschler et al. (2001) | 46 manual wheelchairs | Twenty-seven of 46 wheelchairs failed the MDT and CDT tests. Twenty-eight of 38 wheelchairs tested until failure incurred frame failures. |
| Wang et al. (2010) | 154 manual wheelchairs | Seventy-five of 154 wheelchairs failed the MDT and CDT tests. No evidence on type of failures was included. |
| ISO testing of wheelchairs produced and used in LREs | ||
| Toro et al. (2013) | Two HWC models | Both wheelchairs failed MDT. Failures noted were wheel coming off axle, flat pneumatic insert and tyre, right hub failure, castor tyre wear out and castor fork crack. |
| Zipfel et al. (2007) | One HWC | Wheelchair failed on MDT. Cross brace failure occurred. |
| ISO testing of wheelchairs used in resourced countries | ||
| Fitzgerald et al. (2001) | Sixty-one manual wheelchair models from four manufacturers: 25 HWCs, 22 UWCs and 14 LWCs | Eighty-three per cent of the HWCs, 61% of the LWCs and 24% of the UWCs failed MDT. Twenty-one Class I failures, 29 Class II failures and 45 Class III failures were noted. Castor assembly and frame failures were found. |
| Cooper et al. (1996b) | Six HWCs and nine UWCs | All HWCs failed the MDT. One of nine UWCs failed on CDT. Failures with footrest weld, castor spindles, side frame, cross braces and castor spokes were reported. |
| Cooper et al. (1997) | Three samples of three LWC models | Eight of nine LWCs failed MDT and CDT tests. Several side frame failures occurred in weld areas, one castor spindle failure and one cross brace failure. |
| Gebrosky et al. (2013) | Three samples of three LWC models | All wheelchairs passed the strength tests. Seven of nine LWCs failed the MDT and CDT tests. Several frame failures were observed. |
| Liu et al. (2008) | Three samples of four aluminium rigid UWC models | All wheelchairs passed impact strength tests and brake fatigue tests. Five of 12 chairs failed MDT and CDT tests. |
| Cooper et al. (1999) | Three samples of four UWC models | One of 12 UWCs failed MDT and CDT tests. Castor stem failures, weld, rear wheel bearing and frame failure were noted. |
| Liu et al. (2010) | Three samples of three titanium rigid UWC models | All wheelchairs passed the strength tests. Nine of 12 UWCs failed the MDT and CDT tests. Several backrest cane failures were noted. Sliding footrests and spoke failures on rear wheels were noted. |
Source: Authors’ own work
ISO, International Organization for Standardization; MDT, multidrum test; CDT, curb-drop test; LRE, less-resourced environments; HWC, hospital style wheelchair; LWC, lightweight wheelchair; UWC, ultra-lightweight wheelchair.