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Oxygen Monitors now Required for Nitrogen, Argon, Helium, and CO2 use in Denver

  • By : PureAire Monitoring Systems
  • Posted on : July 24, 2017
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The Colorado city of Denver recently passed a new law that requires facilities that use insert gas to install oxygen deficiency monitors wherever these gases are used in excess of 100 pounds. Learn what the new law requires from businesses and how an oxygen sensor protects your employees, your business, and your peace of mind.

What Denver’s New Law Requires

The law specifically applies to Colorado commercial, industrial, or manufacturing facilities that use inert gases, including nitrogen, argon, carbon dioxide, and helium. Facilities covered by the new law include water treatment plants, laboratories, and food processing plants.

Fire suppression systems and medical gas systems are not covered by the Denver law.

Under the new law:

  • Inert gas storage tanks must be placed in approved locations, whether stored inside or outside of the building
  • Storage containers must be secured to prevent tip-overs
  • All valves and tubing used with the gas system must meet applicable standards
  • Gases must vent outside the building
  • All areas where gas is used must either have an oxygen deficiency monitor or continuous ventilation system, which keeps the oxygen levels in the room steady
  • Oxygen alarms should be visually inspected daily by trained staff members
  •  Storage tanks, piping, and other parts of the system must be checked on a monthly basis
  • Tests of the system must be conducted regularly with either air or an inert gas

The Denver law sets out regulations for the type of oxygen deficiency monitor, plus where and how to use them. Acceptable monitors must be installed in any location where an inert gas leak could result in an oxygen deficient environment where public health could be at stake.

Oxygen detectors must be on an approved device list and directly connected to the electrical supply and fire alarm system for the site. The oxygen detectors must be permanently mounted to the wall at a height which is consistent with the given gas’s vapor density, so they can work properly. The devices must be located within their specified ranges of operation, in order to ensure the monitors can work as intended.

The law prohibits self-zeroing or auto calibrating devices, unless they can be spanned or zeroed to check that the oxygen monitor is working as it should be. All installed oxygen monitors must be calibrated regularly to ensure safe and reliable operation.

Alongside mounted alarms, companies must place signage that notifies employees of the oxygen monitor and gives instructions for what to do in the event of an alarm. Typical instructions tell staff to leave the building and call 911 if the alarm is going off.

Signs notifying employees of the risk for oxygen deficiency must be posted anywhere inert gas is stored or used.

To further protect employees, the Denver law mandates that gas be transported, filled, or moved only by qualified individuals who follow protocol. All equipment, including piping systems, must be inspected for competency and the organization must maintain records for a period of three years.

Why an Oxygen Monitor is a Practical Suggestion

Oxygen deficient environments occur when an inert gas, such as helium, nitrogen, or argon, escapes into the environment and begins to displace oxygen. Since these gases have no odor or color, there is no way that staff working in the room can tell something is leaking. As the oxygen levels fall, employees can experience confusion and respiratory distress, resulting in death by asphyxiation.

An oxygen monitor tracks ambient levels of oxygen and sets off an alarm when oxygen levels fall below the safe threshold, thus protecting employee safety. Since employees can both hear and see the alarm, they will know there is a problem even if they are operating loud equipment that overrides the noise of the sensor.

Oxygen monitors are simple solutions to pressing problems faced by organizations that rely on inert gases and want to mitigate their risk.

PureAire’s oxygen sensors are cost-efficient and high quality. They are designed with a zirconium sensor, which is capable of lasting for as long as 10 years. PureAire’s oxygen sensor is accurate in diverse environments, from storage freezers to basements. The sensor functions between -40 and 55 C. While PureAire’s oxygen monitors do not need to be calibrated, they are capable of calibration, thus eligible for use in Denver.

PureAire’s monitors need little maintenance to work reliably once they are installed using the included wall-mounting brackets, and they are not affected by changes in the barometric pressure, a known problem with other types of oxygen sensors. PureAire’s products can be set to measure oxygen levels of either 18 percent or 19.5 percent (which is the OSHA action level), to comply with standards.

To learn more about oxygen monitors from PureAire, and view specifications, go to