Abstract:
Petrol station attendants’ exposure to gasoline vapours while refuelling vehicles has
raised health concerns, especially in tropical countries like Saudi Arabia. This is due to the
increase of gasoline vaporisation by the high temperatures and related weather conditions.
This represents an increase risk of inhaling more vapours than its counterpart temperate
countries. Furthermore, exposure during extended working hours (12 hrs shifts), with no
vapour recovery system and the handling of gasoline containing a high percentage of
volumes of toxic substances (e.g. BTEXs) have not been adequately addressed previously
in Saudi Arabia. Therefore, this study was designed and carried out to investigate the
validity of this concern by assessing and quantifying full shift exposures to gasoline vapours
during the petrol filling process. Different exposure assessment methodologies were
employed and evaluated for their suitability. The study assessed the exposures of 41
attendants via passive, active, and direct reading methods at twelve petrol stations with both
high and low sales in the Eastern Province of Saudi Arabia. The study was conducted during
the winter and summer months to test the seasonal variation of the pattern of exposure. The
effects of the quantity of gasoline sold, the locations of the stations, weather variations (e.g.
wind speed, temperature, and humidity) were tested. A purpose built mini-weather stations
and modified thermometres were utilized to accurately monitor the prevailing weather
conditions. Forward-looking infrared (FLIR) thermal image cameras were utilised to
visualise the size and movement behaviour of the vapour plumes during petrol refuelling.
Furthermore, analytical lab trials were carried out to characterise the gasoline vapour
component under different temperatures. These were used to propose a new OEL. The
geometric means of the personal passive results for BTEX and MTBE (0.18 ppm, 0.24 ppm,
0.09 ppm, 0.18 ppm, 1.57 ppm, respectively) were found to be relatively higher than those
reported previously for Europe and North America. These results are discussed in the
context of the impact that such exposure will have on people involved in this industry in
petrol stations in Saudi Arabia.
