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Trained firefighters use fire apparatus, water supply resources such as water mains and fire hydrants or they might use A and B class foam depending on what is feeding the fire. Fire prevention is intended to reduce sources of ignition. Fire prevention also includes education to teach people how to avoid causing fires. [42]
Air pollution can occur naturally or be caused by human activities. [4] Air pollution causes around 7 or 8 million deaths each year. [5] [6] It is a significant risk factor for a number of pollution-related diseases, including heart disease, stroke, chronic obstructive pulmonary disease (COPD), asthma and lung cancer.
In other words, a combustible material ignites with some effort and a flammable material catches fire immediately on exposure to flame. The degree of flammability in air depends largely upon the volatility of the material – this is related to its composition-specific vapour pressure, which is temperature dependent
Ventilation is a part of structural firefighting tactics, and involves the expulsion of heat and smoke from a burning building, permitting the firefighters to more easily and safely find trapped individuals and attack the fire. It is frequently performed from the outside of a burning building while the fire is being extinguished on the inside.
Even with high velocity water, it can still become polluted, even if the levels are indeed lower. In using water as a main source of fire fighting, it is clear that there will always be some level of toxicity in the water that is utilized in the process of stopping these fires. Ultimately, the best method of lessening fire-water is lessening fires.
For example, water pollution with toxic chemicals is an anthropogenic hazard as well as an environmental hazard. One of the classification methods is by specifying the origin of the hazard. One key concept in identifying a hazard is the presence of stored energy that, when released, can cause damage.
Hazards have the potential to cause adverse effects only if they come into contact with populations that may be harmed. For this reason, hazard identification includes the development of a conceptual model of exposure. [8] Conceptual models communicate the pathway connecting sources of a given hazard to the potentially exposed population(s).
In most cases, it is the ambient air, and in particular one of its components, oxygen (O 2). By depriving a fire of air the fire can be extinguished, such as when covering the flame of a small candle with an empty glass. To the contrary, if air is blown over a wood fire (as with bellows), the fire is activated by the introduction of more air.