Good morning,

We recently had an incident where a researcher was momentarily trapped in an elevator while transporting a 230 liter Dewar of liquid nitrogen. Thankfully the researcher walked out of the elevator a few seconds later.

This incident raised a concern about the potential for asphyxiation if an entrapment occurred and the Dewar released nitrogen gas into the elevator cab (unlikely but need to prepare). We have elevator rescue protocols in place but the response time depends on the time of day.

Has anyone addressed this type of concern?

Martin W. Bell, M.S. CIH CSP 

Director, Environmental Compliance

Department of Environmental Health and Safety

Drexel University

400 North 31st Street

Philadelphia, PA 19104

Tel: 215.895.5892 | Fax: 215.895.5926

Mobile: 215-778-4278

drexel.edu/facilities/healthsafety