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PEF calls this category Photochemical ozone formation. The metric is identical and reported in kg NMVOC eq. Only the naming differs.

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Definition

Photochemical Ozone Creation Potential (POCP), also known as Summer Smog, measures the ability of a substance to form ground-level ozone (O₃) through reactions with sunlight. It is expressed in kilograms of non-methane volatile organic compound equivalent (kg NMVOC eq) using ReCiPe 2016 characterization factors.

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Environmental Mechanism

Ground-level ozone forms when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react in the presence of sunlight. This process leads to:
  • Formation of photochemical smog
  • Respiratory problems in humans
  • Damage to vegetation and crops
  • Reduced agricultural yields
  • Material degradation (rubber, plastics, textiles)
  • Reduced visibility in urban areas
Unlike stratospheric ozone (which protects Earth from UV radiation), ground-level ozone is a harmful air pollutant.

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Calculation in GREENZERO Journey

GREENZERO Journey calculates POCP by:
  1. Identifying all VOC and NOx emissions throughout a product’s lifecycle
  2. Converting each emission to its NMVOC equivalent using characterization factors from ReCiPe 2016
  3. Summing all NMVOC equivalents to determine the total POCP
About ReCiPe 2016ReCiPe 2016 is a life cycle impact assessment (LCIA) method that provides characterization factors for converting inventory data into environmental impact indicators. It is not a methodology itself, but rather a comprehensive database of impact assessment factors developed by Dutch research institutes.The method provides characterization factors that translate emissions and resource use into standardized impact units (e.g., kg CO₂ eq. for climate change, kg SO₂ eq. for acidification). GREENZERO Journey follows ISO 14040/44 methodological standards while using ReCiPe 2016 characterization factors for impact calculations.

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Environmental Cost Conversion

The POCP impact is converted to environmental cost using the CE Delft cost factor: CE Delft Cost Factor for POCP: €0.42 per kg NMVOC eq. This factor represents the societal cost of damage from photochemical ozone formation, including:
  • Healthcare costs from respiratory diseases
  • Lost productivity due to illness
  • Agricultural crop losses
  • Damage to materials and infrastructure
  • Ecosystem damage

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Example Calculation

For a product with a POCP of 0.2 kg NMVOC eq. per piece: 
Environmental Cost = POCP × CE Delft Factor
Environmental Cost = 0.2 kg NMVOC eq. × €0.42/kg NMVOC eq.
Environmental Cost = €0.08 per piece

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Interpretation

Photochemical ozone formation is primarily an urban and regional issue, with impacts concentrated in densely populated areas during warm, sunny periods. Key contributors to POCP in product lifecycles typically include:
  • Transportation emissions (especially diesel vehicles)
  • Solvent use in manufacturing
  • Fossil fuel combustion
  • Oil and gas production and distribution
  • Chemical manufacturing
  • Printing processes

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Reduction Strategies

Common strategies to reduce POCP include:
  • Emission controls on vehicles and industrial sources
  • Low-VOC solvents and materials
  • Improved fuel efficiency
  • Vapor recovery systems
  • Process optimization
  • Public transportation and carpooling

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Data Quality Considerations

When interpreting POCP results, consider:
  • Regional and seasonal variations in impact
  • Urban vs. rural emission locations
  • Meteorological conditions affecting ozone formation
  • Background NOx and VOC levels
  • Temporal aspects of emissions (summer vs. winter)
POCP often correlates with other impact categories, particularly:
  • Human Health (Respiratory effects)
  • Acidification Potential
  • Global Warming Potential
  • Particulate Matter Formation
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