Evaluation of the effects of repeated disinfection on medical exam gloves: Part 2. Changes in mechanical properties

Abstract

Many healthcare professionals have been forced, under acute shortages, to extend medical exam gloves beyond their intended single use. Despite limited available literature, the CDC proposed a set of guidelines for repeated exam gloves use, indicating a maximum number of treatments for three widely available disinfectants. This study examines how these treatments affect the mechanical properties of latex and nitrile gloves. Furthermore, an acceptability threshold is proposed for changes in tensile property, specifically elastic modulus, as an indication of degradation. This proposed criterion was also applied to similar studies available in the literature to determine applicability and aid in recommendation development. Three different latex glove brands and three nitrile brands were exposed to repeated treatments of an alcohol-based hand rub, diluted bleach, or soap and water. Tensile tests of samples cut from untreated and treated gloves were performed to assess the change in elastic modulus induced by each treatment. The findings suggest that latex gloves performed well within the CDC recommended guidelines of six repeated treatments for an ethanol-based hand rub and 10 repeated treatments of either dilute bleach or soap and water. Nitrile exam gloves, on the other hand, showed significant changes in elastic modulus, with more inconclusive results among brands. This was especially true for treatment with dilute bleach and soap and water. Further research is needed to investigate the effects of disinfection products on the mechanical integrity of nitrile exam gloves. The results support the use of five repeated treatments of ethanol-based hand rub for nitrile exam gloves, a lower threshold than currently recommended by the CDC. This research also supports that the CDC recommendation of 10 repeated treatment with soap and water is appropriate for latex exam gloves, but not for nitrile exam gloves. Occupational safety and health professionals involved in the selection of disposable exam gloves for infection control should consider the compatibility of the glove polymer type with available disinfectants, especially if extended use with repeated disinfection becomes necessary.

Keywords:

• COVID-19
• disinfectant
• elastomeric
• extended use
• PPE
• tensile

Acknowledgments

This project was funded by the Stanford University Center for Innovation in Global Health and the Global Health Equity Scholars Program via the Fogarty Global Health Equity Scholars Program FICD43TW010540. In addition, the authors would also like to acknowledge the support provided by two grants: (1) Pathways to STEM Careers, funded by HSI STEM program of DOE; and (2) the grant Engaged Learning to Promote STEM Graduation (ELPSG), funded by HSI program of NSF. There are no relevant financial or non-financial competing interests to report.

Data availability

The authors confirm that the data supporting the findings of this study are available within the article and its supplementary materials.