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.
The function of a vapor barrier is to retard the migration of water vapor, which are not typically intended to retard the migration of air. This is the function of air barriers. Air is mixed with water vapor. When air moves from location to location due to an air pressure difference, the vapor moves with it. This is a type of migration of water vapor. In the strictest sense air barriers are also vapor barriers when they control the transport of moisture-laden air.