key words 10

• acoustic fatigue


  stress cracking of a material caused by repetitive vibrations induced by sound
• activated carbon filter

  a filter that reduces emissions of pollutants
• acute


  exposure to a substance or symptoms that appear rapidly
• adsorption


  the process where a substance fixes onto a surface
• As low as reasonably achievable (ALARA)


  an approach to control pollution where levels are kept as low as practically achievable

  e.g ionising radiation
• baffle mounds


  embankments that absorb and deflect noise
• bag filter


  a method reducing atmospheric pollution caused by smoke and particulate matter
• best available technology not entailing excessive cost (BATNEEC)


  an approach to pollution control where control technology is used that achieves the lowest emission levels, without costing so much that further marginal gains would risk their financial viability
• bioaccumulation

  the increase in concentration of a substance in living tissue as it is absorbed and stored faster than it is broken down and excreted
• biodegradable


  a material that can be broken down by living organisms

  -> usually bacteria
• biomagnification


  the progressive bioaccumulation of a material along a food chain

  -> e.g organochlorine insecticides, PCBs, heavy metals
• bioremediation


  cleaning up a contaminated site using living organisms that chemically degrade the pollutants or plants that absorb the pollutants

  -> e.g bacteria
• biotic index

  a measure of pollution based on the presence, abundance and state of health of selected living organisms

  -> e.g lichens for acid rain

  -> e.g aquatic invertebrates for water pollution.
• blue baby syndrome / methemoglobinemia


  a health problem with several possible causes, where the haemoglobin in a baby’s blood does not carry enough oxygen. Nitrates in drinking water can be converted to nitrites which reduce the ability of haemoglobin to carry oxygen.
• bund wall


  a wall that surrounds a tank which contain the contents if the tank leaked or burst
• carbon capture and storage (CCS)


  a method to reduce carbon dioxide emissions by removing the gases and storing them in underground geological structures
• carcinogen


  a substance or energy form that can cause cancer
• catalytic converter


  a device that reduces emissions of pollutant gases from petrol and diesel engines.

  -> e.g platinum, palladium and rhodium catalyse reactions with oxides of nitroge

  -> carbon monoxide and unburnt hydrocarbons
• chronic


  exposure to substance or symptoms that appear over long periods of time
• clean air act 1956


  UK legislation to control smoke pollution by the establishment of smoke zones by making control orders in large urban areas
• constant descent angle


  a method of approaching an airport where the aircraft descends at a constant angle

  -> usually 3 degrees
• contamination


  pollution caused by the pollutant staying in contact or mixing with materials

  -> e.g soil, water and living organisms
• cooling towers


  a method of reducing the temperature of effluent water to reduce thermal pollution and deoxygenation
• critical group monitoring


  method of monitoring pollutants

  -> if people most at risk are same then so is everyone else

  -> e.g radioactive discharges
• critical pathway analysis


  the prediction of the routes that an effluent will take in the environment -> to asses pollution risk
• cyclone separator


  equipment used to remove suspended particles from gaseous effluents
• dB scale


  a logarithmic scale used to measure sound levels
• desulfurisation


  the removal of sulfur or compounds that contain sulfur

  -> e.g sulfur dioxide
• dry flue-gas desulfurisation (dry FGD)


  a method of removing sulfur oxides from effluent gases using a slurry of crushed lime -> mainly calcium carbonate
• electrostatic precipitator


  equipment used to remove suspended particles from gaseous effluents by attracting them to electrically charged wires or plates
• encapsulation


  sealing waste in a solid material to prevent its escape

  -> e.g in glass, cement or plastic
• eutrophication


  process by which nutrient levels in a water body increase to excessive levels such that the growth and subsequent die-off of plants and algae cause deoxygenation.
• exposure


  in ionising radiation control, this refers to an object or person receiving radiation, but not necessarily coming in contact with the source.
• flue-gas desulfurisation (FGD)

  process that removes oxides of sulphur from gaseous effluents
• gonadic


  relating to ovaries and testes
• half life


  time taken for half of a material to be broken down or lsot