What air concentration levels mean

The DEQ uses air quality goals called Ambient Benchmark Concentrations (ABCs) to evaluate emissions by manufacturers.

Benchmarks and health 

  • The ABCs are set at a level that would be expected to produce 1 additional case of cancer per 1,000,000 people, if people were exposed 24 hours per day, 7 days per week, for 70 years.
  • A concentration of emissions higher than an ABC does not necessarily mean that there is an immediate public health risk. However, readings above the ABC benchmark indicate more in-depth analysis is needed.
  • Oregon’s benchmarks are stricter than federal standards.