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Colorado Air Pollution Control Division Unified Data Dissemination Application
PROTOTYPE

Ozone

Ground-level ozone is important because it's a harmful air pollutant that damages human health, particularly the respiratory system, and negatively impacts ecosystems and crops. While stratospheric ozone protects from UV radiation, ground-level ozone, the main component of smog, causes respiratory issues like aggravated asthma and lung damage, and also harms forests and vegetation. Colorado's Front Range is designated as a nonattainment area for the federal ozone standard.
Ozone 101

Ground-level ozone facts:

  • Not emitted directly -- formed by chemical reactions between NOx and VOCs in sunlight
  • Worst during hot, sunny days (May-September in CO)
  • Federal standard: 70 ppb (8-hour average)
  • Colorado's Front Range exceeds this standard
  • "Action Day" alerts issued when levels are unhealthy
Sources of Ozone

Ozone precursors (NOx + VOCs) come from:

  • Motor vehicles and trucks
  • Oil and gas operations (VOC emissions)
  • Industrial facilities
  • Power plants
  • Solvents and paints
  • Wildfires (increasing contribution)

Colorado's high altitude and abundant sunshine create conditions favorable for ozone formation.

How Does Ozone Impact You?

Health effects of ozone exposure:

  • Coughing and throat irritation
  • Worsened asthma symptoms
  • Reduced lung function
  • Increased susceptibility to infections
  • Aggravation of chronic lung diseases

Active individuals and those exercising outdoors are at higher risk. On Action Days, limit prolonged outdoor exertion.

How Is Colorado Addressing Ozone?

Nonattainment Status:

  • Denver Metro/North Front Range designated "Serious" nonattainment
  • State Implementation Plan (SIP) for compliance

Reduction Strategies:

  • Enhanced vehicle emissions standards
  • Oil and gas VOC emission controls (Reg. 7)
  • Summer ozone monitoring network
  • Ozone Action Day public notification program
  • 2014 FRAPPE and ongoing research campaigns