Abstract
Ambient air concentrations of specific C
2–C
6 hydrocarbons (HCs) are reported for various days during the summer months of 1983. The samples are classified as either urban, rural or polluted rural according to the sampling site, meteorological conditions and ozone levels. Generally, both the concentrations and HC/acetylene ratios are similar to those reported by other workers for comparable sites. The alkane/alkene ratio at the rural site exceeded that for the urban site and it is concluded that the major contribution to HCs at the former site is advection from distant sources. It appears that the main source of propane in rural areas is natural gas, with about 4.5–9 ppbC unaccounted for by this source.