From: Ellen M. Sweet <ems325**At_Symbol_Here**>
Subject: Re: [DCHAS-L] Space Requirements for in-use gas cylinders (nonflammable)
Date: Thu, 28 Oct 2021 14:40:30 +0000
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU>
Message-ID: MN2PR04MB6285EF1584F689B55EDC4C129A869**At_Symbol_Here**

It just so happens that our local AHJ put together the New York State requirements for CO2 for an unusual application here.

"Code requirements for carbon dioxide:


2020 NYS Fire Code

5307.4 Carbon Dioxide Enrichment Systems

The design, installation and maintenance of carbon dioxide enrichment systems with more than 100 pounds (45.4 kg) of carbon dioxide, and carbon dioxide enrichment systems with any quantity of carbon dioxide having a remote fill connection, shall comply with Sections 5307.4.1 through 5307.4.7. 

5307.4.1 Documentation

The following information shall be provided with the application for permit:

  1. Total aggregate quantity of liquid carbon dioxide in pounds or cubic feet at normal temperature and pressure.
  2. Location and total volume of the room where the carbon dioxide enrichment operation will be conducted. Identify whether the room is at grade or below grade.
  3. Location of containers relative to equipment, building openings and means of egress.
  4. Manufacturer's specifications and pressure rating, including cut sheets, of all piping and tubing to be used.
  5. A piping and instrumentation diagram that shows piping support and remote fill connections.
  6. Details of container venting, including but not limited to vent line size, material and termination location.
  7. Alarm and detection system and equipment, if applicable.
  8. Seismic support for containers.

5307.4.2 Equipment

Pressure relief, vent piping, fill indicators, fill connections, vent terminations, piping systems and the storage, use and handling of the carbon dioxide shall be in accordance with Chapter 53 and NFPA 55. 

5307.4.3 Gas Detection System

gas detection system complying with Section 916 shall be provided in rooms or indoor areas in which the carbon dioxide enrichment process is located, in rooms or indoor areas in which container systems are located, and in other areas where carbon dioxide is expected to accumulate. Carbon dioxide sensors shall be provided within 12 inches (305 mm) of the floor in the area where the gas is expected to accumulate or leaks are most likely to occur. The system shall be designed as follows:

  1. Activates a low-level alarm upon detection of a carbon dioxide concentration of 5,000 ppm (9000 mg/m3).
  2. Activates a high-level alarm upon detection of a carbon dioxide concentration of 30,000 ppm (54 000 mg/m3). 


5307.4.3.1 System Activation

Activation of the low-level gas detection system alarm shall automatically:

  1. Stop the flow of carbon dioxide to the piping system.
  2. Activate the mechanical exhaust ventilation system.
  3. Activate an audible and visible supervisory alarm signal at an approved location within the building.

Activation of the high-level gas detection system alarm shall automatically:

  1. Stop the flow of carbon dioxide to the piping system.
  2. Activate the mechanical exhaust ventilation system.
  3. Activate an audible and visible evacuation alarm both inside and outside of the carbon dioxide enrichment area, and the area in which the carbon dioxide containers are located. 

5307.4.4 Pressurization and Ventilation

Rooms or indoor areas in which carbon dioxide enrichment is provided shall be maintained at a negative pressure in relation to the surrounding areas in the building. A mechanical ventilation system shall be provided in accordance with the Mechanical Code of New York State that complies with all of the following:

  1. Mechanical ventilation in the room or area shall be at a rate of not less than 1 cfm per square foot [0.00508 m3/(s m2)].
  2. When activated by the gas detection system, the mechanical ventilation system shall remain on until manually reset.
  3. The exhaust system intakes shall be taken from points within 12 inches (305 mm) of the floor.
  4. The ventilation system shall discharge to the outdoors in an approved location.


5307.4.5 Signage

Hazard identification signs shall be posted at the entrance to the room and indoor areas where the carbon dioxide enrichment process is located, and at the entrance to the room or indoor area where the carbon dioxide containers are located. The sign shall be not less than 8 inches (200 mm) in width and 6 inches (150 mm) in height and indicate:









5307.4.6 Seismic and Structural Design

Carbon dioxide system containers and piping shall comply with the seismic design requirements in Chapter 16 of the Building Code of New York State and shall not exceed the floor loading limitation of the building.


5307.4.7 Container Refilling

Carbon dioxide containers located indoors shall not be refilled unless filled from a remote connection located outdoors."




Ellen Sweet, MS, CCHO

Laboratory Ventilation Specialist

Department of Environment, Health, and Safety

Cornell University

American Chemical Society, Division of Chemical Health and Safety




From: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**Princeton.EDU> On Behalf Of Margaret Rakas
Sent: Thursday, October 28, 2021 10:11 AM
To: DCHAS-L**At_Symbol_Here**Princeton.EDU
Subject: [DCHAS-L] Space Requirements for in-use gas cylinders (nonflammable)


Good morning,


Are there any requirements or best practices for in-use gas cylinders with respect to sq footage of lab space?  I have a PI who wants to put 3 gas cylinders (2 compressed air, 1 CO2) in a very small (138 sq ft) space where there will be a light sheet microscope (the gases are for the microscope).  I am fairly certain (but am short on details) the CO2 will be used as a freezing agent for very small amounts of tissue.  Of course the cylinders will be secured, and due to room configuration would be out of the way of the single exit...but I cannot find anything in the regulations regarding a maximum storage capacity...  I am going to bring in our compressed gas supplier to see if somehow we can use one compressed air cylinder to supply two different pressures (I am trying to get those details too..)


If your institution has a light sheet microscope I would love to talk with you!


I could not do my job without this listserv, so thanks everyone in advance.  




Margaret A. Rakas, Ph.D.
Lab Safety & Compliance Director
Clark Science Center
413-585-3877 (p)

--- For more information about the DCHAS-L e-mail list, contact the Divisional membership chair at membership**At_Symbol_Here** Follow us on Twitter **At_Symbol_Here**acsdchas

Previous post   |  Top of Page   |   Next post

The content of this page reflects the personal opinion(s) of the author(s) only, not the American Chemical Society, ILPI, Safety Emporium, or any other party. Use of any information on this page is at the reader's own risk. Unauthorized reproduction of these materials is prohibited. Send questions/comments about the archive to
The maintenance and hosting of the DCHAS-L archive is provided through the generous support of Safety Emporium.