Should I use an O₂ gas detector to monitor for CO₂?

One question we get asked a lot is why can’t I fit an O₂ detector to monitor for CO₂ as CO₂ is an asphyxiant. This article aims to answer this question, along with the toxic hazards of CO₂ and our solutions.

CO₂ and Normal Air

The atmospheres Oxygen level will be depleting either because another gas is leaking into the area, causing displacement of oxygen or the oxygen is being consumed by a fire.

The first depletion alarm at 19.5% represents a drop in Oxygen level of 1.4% by volume or 14,000ppm.

As for CO₂, it is present constantly in the atmosphere at around 450ppm, the first alarm is 0.5% (5000ppm) (TWA) and the second alarm is 1.5% (15,000ppm) (STEL)

At first glance it seems that it would be feasible to set a 0.5% depletion alarm on an O₂ detector to monitor for CO₂. However, this would be dangerous, misguided and potentially fatal. In the event of a CO₂ leak, most of the gas displaced in your application will be Nitrogen as this makes up most of the atmosphere. A much smaller percentage of the Oxygen is displaced. The increase in CO₂ is therefore not matched by a correlating decrease in Oxygen levels, preventing an alarm from sounding.

Toxic Effects of Carbon Dioxide

Because CO₂ is a natural part of our breathing process, it is often not considered as an asphyxiating or toxic gas. However, this can quickly become dangerous in the right conditions.

We breathe background levels of CO₂ in the range of 400 to 1200ppm, and this can increase quickly particularly in enclosed spaces. Our body processes this CO₂ by what’s known as a metabolic function, balancing the pH levels in our bloodstream, and ensuring our blood is kept at a neutral level. Too much CO₂ can throw off this balance, making your blood too acidic and leaving long term damage to your organs if left unchecked.

The Legal requirements of CO₂ detecting

A document produced by the UK HSE titled: Assessment of the Major Hazard Potential of Carbon Dioxide provides more detail on CO₂ as a toxic gas.

IGD’s CO₂ Detectors

At IGD, we have been manufacturing gas detection for over a century and CO₂ detectors even before the Second World War, always being at the forefront of gas detection technology. We have multiple options for CO₂, from networked monitors in the form of our 750 addressable series which provide enhanced capability while reducing your overall costs. The 750 series also provides continuous 24/7 monitoring of the area and can activate ventilation and automatic shut of a process if a leak is detected.

If you are transporting CO₂ gas bottles, working with dry ice or in the beverage industry, then the portable iGAS CO₂ detector is the ideal solution. Featuring a leading 14 day run time on a single charge, USB re-chargeable and IP68 for durability. Available to purchase online today from our online store.