Candles are simple inventions which have been in use for thousands of years, primarily for the purpose of illumination. This was because thousands of years ago, there were not many options where indoor illumination was concerned. Open fires were perhaps the first available choices for indoor illumination, particularly in the earliest prehistoric eras. However, candles were later brought to life, with the evolution of technology over time. Candles give light through their flames, and flames cannot burn without oxygen, which begs the question: ‘can a candle burn all the oxygen in a room?
THE LINK BETWEEN CANDLES AND OXYGEN
Candles used to be one of the major sources of indoor illumination before the invention of the light bulb and the utilization of electricity for lighting. For this reason, the place of candles in ancient times was a lot more intrinsic and essential than it is now. However, the evolution of technology over millennia has ensured that candles will always have a place in history and society. Asides illumination, candles are used in aromatherapy which is a process which makes use of scents and fragrances from plant extracts and essential oil. Candles such as these, which have been infused with scents and fragrances, are called scented candles and they usually give off those fragrances when they burn.
However, the burning of a candle itself is a process which cannot take place in the absence of oxygen. A candle burns with a flame and fire requires fuel to burn. In the case of candles this fuel comes from the materials used to make the candle wicks as well as the candle-wax. These materials have to support burning. Also, the process of combustion – through which flames are created – requires oxygen. Continued burning also requires oxygen for sustenance. Burning or combustion cannot take place in the absence of oxygen. This inability of fire to burn in the absence of oxygen is what forms the basis of using carbon gas as a component of some fire extinguishers.
When we consider how fire needs oxygen to burn, we may begin to wonder about many things such as, ‘Exactly how much oxygen does a single candle require to burn?’ and ‘Can a candle burn all the oxygen in a room?’
CAN A CANDLE BURN ALL THE OXYGEN IN A ROOM?
Theoretically and practically, it is possible for a candle to burn all the oxygen in a room. However, this depends on several factors. One of those factors includes the type of room in question. It would go to the reason that it would take a longer time for a single candle to burn off all the oxygen in a bigger room, compared to a smaller room. In which case, after all the oxygen in the room has been utilized, the flame will die. However, this situation is really difficult to achieve because for all the oxygen in a room to be removed, it means that there is no means through which air can go into the room. This situation goes beyond the state of unopened windows, it means that even the spaces lining the windows and the air spaces under the doors also have to be blocked. In scenarios such as this a single person in such a room is likely to suffocate eventually; even without the presence of a burning candle. This is because breathing – or rather, respiration – occurs based on the same basic principles of combustion. That is, oxygen is being utilized to feed the process, however oxygen is not part of the major gases given off.
Another factor that may affect the ability of a candle to burn all the oxygen in a room is the number of candles. In a situation where no windows are open, no air conditioners are in use and all possible air spaces or holes through which fresh air can enter into a closed room are sealed, the amount of candles that are lit in the room can affect the speed at which all the oxygen will be removed. The more the candles, the faster all the oxygen in the room is burned.
OTHER FACTORS WHICH CAN INFLUENCE THE RATE AT WHICH A CANDLE CAN BURN ALL THE OXYGEN IN A ROOM
Asides the number of candles which are being lit, there are other factors which can affect the rate at which a candle can burn all the oxygen in a room. However, one of the most important of such factors is the presence of living things in the room.
Fires are not the only things that utilize oxygen and have the ability to burn it away. Living things also require oxygen and they are perhaps the largest consumers of oxygen on the planet. The types of living things that require oxygen are numerous and vary in terms of size – i.e. they may be microscopic or macroscopic – and the degree to which they require oxygen. The major and most visible ones among them fall under the categories of plants and animals.
There are many types of animals and many subgroups and classification of each kind. Each one requires oxygen for respiration to a very considerable extent. Many animals – and even humans – cannot for without oxygen for more than a few minutes at a time. Plants also require oxygen to a large extent as it helps them in various processes including respiration and nutrition. Therefore when other living things are kept in an enclosed area there is a high risk of suffocation if air – especially oxygen – is not provided on time. Thus when you add a candle – or more than one candle – into the mix, in such a scenario, it will only serve to hasten the time required for all the oxygen in the (enclosed) room to be used up.
THE CONSEQUENCES OF BURNING OFF ALL THE OXYGEN IN A ROOM
This kind of situation – where all the oxygen in a room is burned off and a living thing is in that enclosed space – can be very deadly to the living thing involved as it may result in its demise. However, the candle will simply go out as soon as there is no oxygen left to burn. As for the enclosed room, air can be returned into it as soon as its windows and doors are open and air can flow into it.