Meningitis is a disease caused by the inflammation of the protective membranes covering the brain and the spinal cord. While most people with meningitis recover, it can cause serious complications, such as brain damage, hearing loss or learning disabilities. A vaccination is the most effective way to protect yourself against certain types of meningitis.
Primary & Secondary pollutant. Definition: A primary pollutant is an air pollutant emitted directly from a source. A secondary pollutant is not directly emitted as such, but forms when other pollutants (primary pollutants) react in the atmosphere.
Atmospheric air contains some moisture in the form of water vapour. HUMIDITY is the amount of water vapour in the air. (I know what you are thinking - yes, even the Sahara Desert has an annual average of 25% relative humidity) RELATIVE HUMIDITY is the amount of water vapour in the air relative to what the air can hold. Warm air can hold more moisture than cold air. For instance, let's say that a certain parcel of air can hold 30 grams of water vapour per cubic meter, but has only 15 grams of water vapour per cubic meter of air when measured.