Development of a method for kinematic analysis of the doffing process for a specific garment style

Garment doffing is recognized as an important element of safety, yet little information exists about doffing. The purpose of this research was to develop a method for kinematic analysis of the doffing process. The specific objectives were to 1) identify the basic critical movements involved in the doffing process of a selected garment style, 2) quantify the movement pattern. and 3) assess the validity of the method and the reliability of the data.

To study the movements involved in doffing a nightgown, doffings were recorded by video and WATSMART® (electro-optical) cameras. Relative angular displacement vs. time data were generated from video recordings using the Posture Taxonomy instrument, and from WATSMART recordings using a computer program. The movement experienced by the shoulder and elbow joints were close to the maximum physiologically possible. Twelve critical movements were identified using Roebuck’s terminology.

The construct validity of the method was shown to be satisfactory by the convergence of the WATSMART and video position vs. time data. The reliability of the data was assessed in terms of intra- and inter-trial consistency. WATSMART was found to be sensitive enough to discern the differences in consistency due to garment style, subject fatigue, and differing configurations of IREDs.

Based on the satisfactory convergence of the data and consistency of the data, it was concluded that using the WATSMART system to kinematically analyze the doffing process was feasible. The degree of fidelity of the garments needs to be established before the method can be adopted for general use, however.