The article presents two investigations by CONCAWE (the oil companies' European organisation for environment, health and safety) of benzene emissions from cars and of back-end volatility. Statistical analyses were made of the results of many recent tests of exhaust emissions from petrol engines. Data were obtained from 21 modern non-catalyst cars and 34 cars with catalysts. Correlations were derived to describe the relationships, as functions of fuel composition, for benzene: (1) in mg/km; and (2) as a mass percentage of total exhaust hydrocarbons. The results confirm that catalyst cars cut benzene exhaust emissions by 85%. The correlations are statistically robust, and show that the relative influence of benzene concentration in the petrol is 16.5 to 18 times greater than the effect of non-benzene aromatics (NBA) concentration for non-catalyst cars, and 8 to 10 times greater for catalyst cars. The volatility or distillation of the intermediate and heaviest petrol fractions are often respectively called 'mid-range volatility' and 'back-end volatility'. Recent data, from CONCAWE and others, show that mid-range and back-end volatility have a small but clear effect on car exhaust emissions. The emission effects seem to be described best by distillation parameters in the range T50 to T70 (or E100 to E120).

  • Corporate Authors:


    Brussels,   Belgium 
  • Publication Date: 1995-10


  • English

Media Info

  • Pagination: p. 12-3
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00723164
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Jul 26 1996 12:00AM