Fault Tree for Wheelchair Mounted Transfer Assist Device Mike Anderson Andrew Feola Jill Marion Bryan Shelly BioE1161 April 18, 2006

Patient Hazard A B C D

(power wheelchairs only) Power Hazards A Shock from wheelchair (power wheelchairs only) Power failure of the system Failure to automatically shut Off power Power system malfunction

Transfer board doesn’t Mechanical Failures Transfer Board Position Transfer Board Mechanics Wheels not locking In place properly Failure due to cyclic stress Failure due to ultimate stress Transfer board not in a sturdy position Transfer board doesn’t lock in position

Patient Errors C C.1 Injury during transfer Fall while performing Clothing getting stuck in the seat/hardware Incorrect use of Transfer board Improper transferring technique

C.1 Transfer board Incorrectly placed Patient attempts to transfer a distance greater than 18” Transfer board slides from underneath patient

Cushion seat wears down Body Injury D Increased pressure on patients back/hip Pressure Sores Cushion seat wears down Seat cushion left in an incorrect position