Oxygen is the most fundamental requirement of human life. While we can survive without water for a few days, and food for a few weeks, just a few minutes without oxygen is fatal. It is vital that good air quality is maintained wherever people are working.
If too much carbon dioxide is in the air, the symptoms are similar to there being too little oxygen: headaches, dizziness, confusion and loss of consciousness, leading potentially to death. Note that carbon dioxide poisoning can occur even when oxygen levels remain healthy. Being heavier than air, carbon dioxide can accumulate in below surface sites, so it is important to provide a continuous supply of fresh air.
Carbon monoxide is a poisonous gas produced by burning of carbon-based fuels like gas, petrol, wood and coal. When inhaled, it prevents blood from supplying oxygen to cells, tissues, and organs. In poorly ventilated conditions where there is a source of carbon monoxide, such as a faulty heater or an engine running, the levels can quickly rise to become fatal.
Each of the three gases is odourless, tasteless and invisible, making it practically impossible for any of the body's senses to detect when the levels are dangerous. In confined spaces, pushing fresh air to the remotest point is vital to ensure that fresh air is circulated throughout and concentrations of dangerous gases are effectively diluted. This can be achieved by using powerful fans to supply fresh and extract polluted air.
For more information on how to maintain safe levels of these gases, download our full white paper.
The amount of fresh air required should be calculated to determine the number and power of fans required for its delivery. The fans themselves should be sited downwind of any generators used, so that no exhaust fumes contaminate the air being supplied.