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Regulator Use Procedures for
Non-Hazardous Gases
Prepared by Wayne A. Buchanan, I.E.C.
This document is intended to serve as a general guideline for the use
of compressed gas regulators. It is assumed that the system or apparatus
to which the gas cylinder is being connected has been properly designed
and tested for the high pressures and other hazards associated with
compressed gas. This is not a guide for the use of hazardous gases or
systems using such gases. It is the responsibility of the operators to
obtain the proper training in such situations. Any reference to hazardous
gases is purely incidental. Regulators for oxygen service require special
considerations. Consult your gas supplier and MSDS. This document should
be read completely before proceeding.
Safety Precautions
WEAR APPROVED EYE PROTECTION AND SAFETY APPAREL AS RECOMMENDED BY
THE MSDS.
Know the specific hazards associated with gas to be used. Consult the
MSDS that was shipped with the gas or obtain a copy from Occupational
Health & Safety.
Leak test the system on which the gas is to be used.
Make sure the regulator to be used is suitable for the application.
Most gas company catalogs give this information for both gases and
regulators or, if not, consult the vendors directly.
Categories of Regulators
A single-stage regulator will usually require delivery pressure
adjustment as the cylinder pressure decreases.
Two-stage regulators will usually require no adjustment.
Installation and Operation
Properly secure the cylinder to a stable surface.
Remove the cap from the cylinder.
Make sure the cylinder valve is tightly closed.
Remove the cylinder valve cap or plug if present.
Check the CGA regulator fitting and the fitting surface of the
cylinder valve for damage, especially the threads and seat. If damaged,
return the cylinder for replacement. Remove any loose debris from the
threads and seat.
Close the regulator by turning the adjusting knob or handle
counterclockwise.
Close the outlet valve fully in a clockwise direction. If a
valve is not present, one should be purchased.
Connect the regulator to the cylinder. DO NOT FORCE the connection.
You should be able to make the initial connection by hand. If not, then
you are using the wrong regulator, or the threads on the cylinder valve or
CGA connection or both are damaged and should be replaced. Tighten until
snug using a regulator wrench, an open end wrench or an adjustable wrench.
DO NOT OVER-TIGHTEN.
NEVER use lubricants or Teflon tape to aid in the connection or
sealing of the CGA fitting.
Check the cylinder valve for leaks around the thread connections into
the cylinder and the valve handle, using an approved soap solution
(available from gas suppliers). If any are discovered, return the
cylinder for replacement.
Hex nuts on the CGA connection with notches in the middle indicate
left hand threads and are tightened in a counterclockwise direction.
Some regulators require gaskets on the CGA connections. These should
be inspected for wear or contamination and be replaced as necessary. USE
THE PROPER REPLACEMENT GASKET. Do not over-tighten, as this could
cause the gasket to extrude in the gas stream. Replace the gasket at each
cylinder change out.
Use the proper fittings on the outlet of the regulator to the system.
Avoid too many connections. The correct fitting can be purchased from the
regulator supplier. Do not make adapters to get to the proper
fitting.
The operator should position himself/herself with the cylinder between
themselves and the regulator. While looking away, SLOWLY open the
cylinder valve in a counterclockwise direction, 1/8 turn. The high
pressure gauge should rise to full cylinder pressure.
Leak check all connections using an approved soap solution or other
leak checking device (hand-held detectors for specific gases, etc.). If
leaks are discovered, depressurize, tighten, then recheck the connections.
If you cannot easily make a leak-tight seal at the CGA fitting, and the
problem is not with the cylinder valve, the CGA fitting should be
replaced. These can be obtained from any gas supplier. DO NOT
OVER-TIGHTEN THE CGA CONNECTION TO TRY AND ACHIEVE A LEAK TIGHT-SEAL.
If no leaks are discovered, open the valve fully to seat the valve,
then close 1/8 turn.
Turn the regulator adjusting knob or handle clockwise to raise the
delivery pressure to the desired working pressure while observing the
delivery pressure gauge. DO NOT EXCEED THE MAXIMUM DELIVERY PRESSURE FOR
THE REGULATOR OR THE SYSTEM.
Check the system for leaks.
Open the outlet valve on the regulator to supply gas to the system.
Delivery pressure may need some adjustment.
Shutdown and Removal
For temporary shutdown (less than 30 minutes), simply close the
outlet valve of the regulator.
For extended shutdown, shut off the gas cylinder valve completely,
open the regulator adjusting valve (to delivery pressure) and outlet
valve, and drain all gas from the regulator through the system. Both
gauges should read zero. Close the regulator by turning adjust knob
counterclockwise and outlet valves.
If replacing the cylinder, follow the procedure for extended shutdown,
remove the regulator from the cylinder, and install the new cylinder as
outlined in the installation procedures above.
In general, a cylinder is considered empty when the cylinder pressure
is 2X the usable delivery pressure. Do not draw down below 2
bar.
For further information, please review the Regulator Inspection Procedures.
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