One change per hour seems very low. Have you considered putting an oxygen sensor in the room with the alarm outside the door?
Tim
Timothy M. Hauser, CHMM
Manager, Environmental, Health & Safety
Promega Corporation
2800 Woods Hollow Road, Madison WI 53711 USA
Timothy.Hauser**At_Symbol_Here**promega.com | Direct (608) 298-4807 | Cell: (262) 844-1665 | Fax: (608) 277-2677
-----Original Message-----
From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU] On Behalf Of Ralph B Stuart
Sent: Friday, March 08, 2013 9:40 AM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: [DCHAS-L] Liquid nitrogen storage
Does anyone have a rule of thumb for a ventilation rate in a room which is being used to store liquid nitrogen containers? Several credible web sources recommend a "well-ventilated area" without mentioning numbers. We have a room under consideration for this purpose with about 1 air change per hour. This seems low to me, but I thought I would sanity check it with DCHAS-L.
Thanks for any help with this.
- Ralph
Ralph Stuart CIH
Chemical Hygiene Officer
Department of Environmental Health and Safety
Cornell University
rstuart**At_Symbol_Here**cornell.edu