Additionally, in an enclosed environment , combustion would reduce the available oxygen in the room eventually resulting in hypoxia.
Hypoxia is a state of oxygen deficiency in the blood, tissues, and cells sufficient to cause an impairment of body functions. Anything that impedes the arrival or utilization of oxygen to the cell places the body in a hypoxic state. All cells require oxygen to function. The central nervous system (made up of the brain and spinal cord) demands a great deal of oxygen (approximately 20 percent of all oxygen that you inhale feeds the brain). If the oxygen supply to the body is reduced, the brain will be one of the first organs to be affected, with the higher reasoning portions of the brain showing degraded function first. This means that judgment and cognitive skills diminish from the very start. There are many conditions that can interrupt the normal flow of oxygen to the cells.
If you are fortunate, you will feel giddy from the lack of oxygen to your brain. If you miss the symtoms, you may just pass out.
Signs of hypoxia can be detected in an individual by an observer. Signs aren’t a very effective tool for hypoxic individuals to use to recognize hypoxia in themselves. Symptoms of hypoxia are the sensations a person can detect while in a hypoxic state. Personal symptoms of hypoxia are as individual as the person experiencing them. A group of people who are hypoxic will, a majority of the time, get the same symptoms. However, the symptoms will appear in a different order and in varying intensities. The greatest benefit in hypoxia training in an altitude chamber is that the order and the intensity of your symptoms will usually remain constant over the years. Therefore, familiarity with one’s own hypoxia “signature” will facilitate the recognition of a hypoxic state during flight.
Cyanosis (bluing effect of the skin)
Executing Poor Judgement
Myoclonic (Muscle) Spasms