StacksVerified U.S. regulatory reference

46 CFR §108.443

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)At least one control for operating a CO2 system must be outside the space or spaces that the system protects and in a location that would be accessible if a fire occurred in any space that the system protects. Control valves must not be located in a protected space unless the CO2 cylinders are also in the protected space.
  2. (b)A CO2 system that protects more than one space must have a manifold with a stop valve, the normal position of which is closed, that directs the flow of CO2 to each protected space.
  3. (c)A CO2 system that protects only one space must have a stop valve installed between the cylinders and the discharge outlets in the system, except on a system that has a CO2 supply of 136 kilograms (300 pounds) or less.
  4. (d)At least one of the control stations in a CO2 system that protects a machinery space must be as near as practicable to one of the main escapes from that space.
  5. (e)All distribution valves and controls must be of an approved type.
  6. (f)Each CO2 system that has a stop valve must have a remote control that operates only the stop valve and must have a separate remote control for releasing the required amount of CO2 into the space protected by the system.
  7. (g)Each CO2 system that does not have a stop valve must be operated by a remote control that releases the required amount of CO2 into the space protected by the system.
  8. (h)Remote controls to each space must be in an enclosure.
  9. (i)Each system must have a manual control at its cylinders for releasing CO2 from the cylinders, except that if the system has pilot cylinders, a manual control is not required for other than pilot cylinders.
  10. (j)If gas pressure is used to release CO2 from a system having more than 2 cylinders, the system must have at least 2 pilot cylinders to release the CO2 from the remaining cylinders.
  11. (k)If the entrance to a space containing the CO2 supply or controls of a CO2 system has a lock, the space must have a key to the lock in a break-glass type box that is next to and visible from the entrance.