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are uncommon. We demonstrated that an oxygen concentra- Disclosures
tion above 45% was required, which is only found in very Dr. Ho serves as the medical director to Axon Enterprises, Inc.
close proximity to a maximally flowing oxygen source. This and owns shares of stock in the company. Dr. Dawes discloses
supports the concept of rapid oxygen concentration diffusion that he serves as an expert medical consultant to Axon Enter-
during supplemental delivery, even with maximum flow rates. prises, Inc. Dr. Driver has no conflicts to declare.
We acknowledge that CEW use in general is not without some
risk, and we advocate limiting sources of ignition in the patient Funding
care environment for general safety reasons. However, we also This work was supported by Axon Enterprise, Inc. who pro-
believe that prohibiting CEW presence or use because of con- vided lab space, commercial product for study, and engineer-
cerns regarding the use of supplemental oxygen is unfounded. ing assistance during the data gathering phase of this study.
Limitations References
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possible. However, we elected to examine oxygen levels using place violence across 65 U.S. emergency departments. Acad
a space that could be fully enclosed to theoretically limit the Emerg Med. 2008;15(12):1268–1274. doi:10.1111/j.1553-2712.
2008.00282.x
diffusion of the supplemental oxygen. We believe that the data 2. Nachreiner NM, Gerberich SG, Ryan AD, McGovern PM. Minne-
we gathered represents the environment most likely to have sota nurses’ study: perceptions of violence and the work environ-
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to a worst-case scenario for a CEW arc to occur from a fire- 45.672
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ing oxygen source in a patient care setting. There may be other Occupational Hazards in Hospitals. Centers for Disease Con-
combustible materials that might have lower ignition thresh- trol and Prevention; 2002. Accessed July 6, 2023. https://www.
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Acknowledgments posure to violence in the emergency medical services (EMS) work-
The authors would like to acknowledge the engineering con- place: a mixed-methods cross-sectional survey. Prehosp Emerg
Care. 2014;18(4):489–494. doi:10.3109/10903127.2014.912703
tributions of Matt Carver and Erinn McIntyre for their help in 15. Grange JT, Corbett SW. Violence against emergency medical ser-
constructing and carrying out the study. vices personnel. Prehosp Emerg Care. 2002;6(2):186–190. doi:
10.1080/10903120290938526
Author Contributions
JH conceived the study concept and obtained funding. JH, DD, PMID: 38865654; DOI: 10.55460/BFZE-IKTR
and BD coordinated and collected the data, and BD analyzed
the data. JH wrote the first draft, and all authors read and
approved the final manuscript.

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