In collaboration with the Netherlands Organisation for Applied Scientific Research (TNO) and Opinium Research, CLASP conducted a study across seven European countries in 2023 to assess the impact of gas cooking on indoor air quality. The research involved monitoring in-home air quality in gas- and electric-cooking households, collecting household and cooking behaviour data, and analysing indoor pollutant concentration levels.

The report tackles several critical questions:

• What are the levels of indoor air pollution in households with gas cooking appliances and how do they compare to households that cook with electric appliances?
• How do these pollution levels compare to established mandatory outdoor air quality standards as well as pollution levels recommended by the WHO?
• Is ventilation enough to mitigate the health risks linked with gas cooking, or is a transition to cleaner cooking technologies necessary?

The report’s key findings provide a compelling call to action:

• Gas cooking often results in indoor air pollution that exceeds WHO air quality limits, putting citizens at risk of severe health issues.
• Many households with gas cooking appliances exceed WHO air quality guidelines for nitrogen dioxide (NO₂).
• Electric-cooking households, in contrast, enjoy significantly better indoor air quality, free from NO₂ pollution caused by kitchen appliances.
• Ventilation alone is insufficient to mitigate the pollution, necessitating a transition to cleaner electric cooking.

To safeguard public health, it’s essential to educate people about the health risks associated with gas appliances and provide them with resources to transition to cleaner and healthier cooking technologies. CLASP calls for collaborative efforts from governments, industry, civil society, healthcare providers, and individuals to improve indoor air quality across Europe.

Additional Resources

TNO Report: Health Effects in Europe from Cooking on Gas – Phase II Field Study

Executive Summary Translations

Dutch, French, German, Hungarian, Italian, Romanian, Slovak, Spanish

Press Releases

Dutch, English, French, German, Hungarian, Italian, Romanian, Slovak, Spanish.

Report Figures Available for Download

Figure 1. Gas cooking appliances directly emit harmful pollutants, whereas PM_2.5 is emitted by the process of cooking food

Figure 2. Criteria for household monitoring selection

Figure 5. Comparison of average NO₂ concentrations in gas- and electric-cooking homes

Figure 6. Average NO₂ concentrations per country and per cooking method in different rooms

Figure 9. Average exceedance of WHO and EU/UK NO₂ limit values in gas- and electric-cooking homes

Figure 10. Average number of exceedance days of the WHO daily guideline value during the 13-day measurement period

Figure 11. Highest hourly CO concentrations found in the kitchen, per country and per cooking method

Figure 12. Average PM_2.5 concentrations in the kitchen, per country and per cooking technology

Figure 14. Overview of ventilation types recorded in the study

Figure 15. Comparison of average indoor-attributed NO₂ concentration throughout the home, by cooker type

Figure 16. Average PM_2.5 concentration in kitchen for all homes cooking on gas and electric hobs

Figure 17. Reasons for using ventilation in the kitchen: results from a 2023 CLASP consumer survey

Figure 18. Average NO₂ concentrations in the Netherlands in the kitchen, living room, bedroom, and outdoors

Figure 19. Map of gas- and electric-cooking households in the Netherlands showing NO₂ levels

Figure 21. Average NO₂ concentrations in Italy in the kitchen, living room, bedroom, and outdoors

Figure 22. Map of gas- and electric-cooking households in Italy, based on severity of NO₂ levels

Figure 24. Average NO₂ concentrations in Spain in the kitchen, living room, bedroom, and outdoors

Figure 25. Map of gas- and electric-cooking households in Spain, based on NO₂ levels

Figure 27. Average NO₂ concentrations in France in the kitchen, living room, bedroom, and outdoors

Figure 28. Map of gas- and electric-cooking households in France, based on severity of NO₂ levels

Figure 30. Average NO₂ concentrations in Slovakia in the kitchen, living room, bedroom, and outdoors

Figure 31. Map of gas- and electric-cooking households in Slovakia, based on severity of NO₂ levels

Figure 33. Average NO₂ concentrations in Romania in the kitchen, living room, bedroom, and outdoors

Figure 34. Average corrected NO₂ concentrations in Romania, taking into account higher levels of outdoor air pollution

Figure 35. Map of gas- and electric-cooking households in Romania, based on severity of NO₂ levels

Figure 37. Average NO₂ concentrations in the United Kingdom in the kitchen, living room, bedroom, and outdoors

Figure 38. Map of gas- and electric-cooking households in the United Kingdom, based on severity of NO₂ levels

Guidance Materials for Participating Households

Field Testing Equipment Overview

Field Testing Equipment Installation Guide

Household Recruitment Questionnaire

Instructional Videos for Participating Households: Dutch, English, Italian, French, Romanian, Slovak, Spanish

Visit our Cook Cleaner Europe page to view additional resources on gas and electric cooking.