Using an Iterative Design Process to Design Safer Working Environments: Lessons Learned from Biocontainment Unit

Maria Wong Sala (SimTigrate Design Lab, Georgia Institute of Technology)

Safe doffing of personal protective equipment (PPE) in a biocontainment unit (BCUs) is a high-stakes complex task that needs to be done precisely and very reliably and requires training and a supportive built environment. However, while doffing the PPE is the most dangerous step in providing care for Ebola patients, little is known about the discrete environmental design requirements that support behaviors reducing contamination risk.

In this presentation, we report on a user-centered, iterative process for understanding the design affordances for these kinds of behaviors and how it was applied to BCU design. We tested the impact of design changes on improving HCW posture, reducing cognitive load and the frequency of behaviors associated with increased risk of contamination during the doffing of PPE.

We observed and analyzed 41 simulated PPE doffing exercises in four Level-1 BCUs and documented interactions between HCWs and the built environment. Later, in a high-fidelity BCU mock-up, we conducted simulations with a sample of 47 college-level students with no PPE training. Students completed the given tasks using four different stabilization aids in different hypothesized optimal layouts with varying degrees of flexibility and space demarcation. We assessed their performance using NASA's Task Load Index (TLX), Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA) and counted the frequency of risky behaviors.

We iteratively modified and tested the doffing area and conducted simulations with 8 trained HCWs. We compared the performance results before and after the design alterations. In the first phase, participants performed best when using the horizontal grab bar or stability bar- both their stability and posture improved.Two-thirds of the participants reported a preference for the more restricted layout, fixed stabilization aid and using color as a visual cue effectively communicates the proper location to stand.