Oxygen Depletion Monitoring – Understanding the Basics

If you are interested in oxygen monitoring, you have probably come across the term ‘oxygen depletion monitor’. The term itself suggests that it is a device which measures oxygen depletion.  In this article I will try to explain in simple, layman’s terms what exactly is oxygen depletion and how it can affect us – so that everyone could have a better understanding of this important topic, not only specialists.

So, let’s see, what is oxygen depletion?

The word depletion has many meanings. In the fields of ecology, medicine and industry (which are related to our ‘oxygen monitoring’ topic) it indicates the exhaustion of a certain resource or chemical element, its consumption at a faster rate than it is replenished or its replacement with another substance or element.

Oxygen is vital for most living organisms on our planet, including those who live in water: it is present not only in the ambient breathing air (the normal concentration of O₂ in the air being 21%), but also in water (being essential for the survival of fish and other water organisms). From the environment, the oxygen is ‘captured’ by our lungs and transferred to the bloodstream, being carried to every cell of the body (the normal blood oxygen levels of a healthy, non-smoking person at sea level ranging between 95%-99%).

Oxygen depletion is the lowering of the oxygen saturation in a certain environment below the normal levels, to a point where it threatens not only the health, but also the very existence of all oxygen-breathing organisms, including human beings.

It’s not a secret anymore that industrial activities are negatively impacting the ecological balance of our planet. Scientists have discovered that the oxygen levels in the atmosphere and the oceans are constantly dropping. During the past years, the oxygen depletion has accelerated, reaching an alarming rate. While some people consider that this phenomenon is a consequence of the increase of CO₂ produced by burning various fuels, recent researches have proven that this is not the only cause. Deforestation and the constant expansion of agriculture are also playing an important role in this dangerous process, though there are many other causes which still remain unclear.

Insufficient oxygen in the breathing air (in some polluted areas the oxygen concentration in the air can drop as low as 10-16%) has a wide range of consequences on our health: from dizziness and headaches to low immunity and vulnerability to all sorts of bacterial and viral infections, various severe diseases (including cancer) and even death.

The same scenario happens in oceans as well. We all have learned in the biology classes that the oxygen dissolved in water is essential for aquatic organisms. Usually, the consumed oxygen is replaced by the oxygen coming from the atmosphere, being also produced by aquatic plants in the process of photosynthesis. However, because of the recent industrial and agricultural pollution, in many aquatic ecosystems the dissolved oxygen is used faster than it can be replaced. One of the major causes of this phenomenon is the dumping of phosphates and other chemicals in water; causing an excessive growth of oxygen-consuming algae, this leads to inevitable oxygen depletion. The hypoxic zones (also called ‘dead zones’ – areas containing oxygen deficient waters) are becoming more and more frequent, usually surrounding big industrial centers and being the main cause of fish kills.

Oxygen depletion is extremely dangerous. Personally, I don’t know if we can talk about a real solution, one that can restore the normal oxygen levels of our planet and its ecological balance. We are too used to the comfort of our materialistic lifestyle, to the speed provided by modern means of transportation and to all the products offered by civilization. This is the main reason why, no matter how hard ecological movements try to save our planet, there will always be people for whom short-term comfort and financial profits will be more important.

However, there are so many things we could do to save the precious supply of oxygen! The first step in this process is awareness; while ignorance and indifference are among the causes of all ecology-related problems. Alternative energy sources could also improve the situation considerably – but that would be extremely unprofitable for all the major oil companies, wouldn’t it?

Oxygen monitoring is another solution: even if it cannot restore the oxygen levels in atmosphere or water to normal, it can certainly warn specialists and protect home consumers from immediate danger.

Nowadays, many people are working in dangerous environments: factories, refineries, furnaces, laboratories and other confined spaces prone to oxygen depletion. In order to protect these people from intoxication and asphyxiation, specialists recommend the use of oxygen depletion monitors – devices which analyze the oxygen saturation in the breathing air or another liquid or gaseous environment and sound an alarm whenever the O₂ levels drop below the safe limit.

Oxygen depletion monitors are used for personnel protection in various industries:  food, automotive and aerospace, electronics, pharmaceutical and medical, plants etc., as well as in rooms situated at low altitudes (basements and pits).

One of the biggest causes of oxygen depletion in confined spaces is the use of cryogenic liquids such as nitrogen. If these liquids are accidentally spilled, they can evaporate and expand extremely fast, depleting the oxygen from the breathing air and causing asphyxiation (or at least gravely affecting the health of the exposed personnel).

An oxygen depletion monitor ( personal or wall-mounted) can detect oxygen deficiency in time, warning everyone about the immediate danger. This device can offer reliable protection for all people working in hazardous conditions.

However, personnel safety in industrial facilities is not the only application of an oxygen depletion monitor. It can also be used by homeowners who have ventless fireplaces. Oxygen depletion is the first problem which arises because of these fireplaces: if they are kept ON longer than recommended, the toxic combustion emissions will deplete the oxygen from the breathing air. That’s why many ventless fireplaces are equipped with ODS (oxygen depletion sensors) which turn the fireplace off when the oxygen saturation in the air drops below the safe limit.

Oxygen monitors cannot save the ecological balance directly and they cannot reverse the oxygen depletion phenomenon; however, by increasing our awareness and protecting us from immediate danger, they can certainly help us improve the situation!