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Gasoline is a volatile complex mixture of hydrocarbon compounds that is easily vaporized during handling under normal conditions. Modern reformulated gasoline also contains oxygenates to enhance octane number and reduce ambient pollution. This study measured the difference in the exposure of customers to gasoline and oxygenate vapors during refueling in service stations with and without vapor recovery systems. Field measurements were carried out at two self-service stations. One was equipped with Stage I and the other with Stage II vapor recovery systems. At Stage I stations there is vapor recovery only during delivery from road tanker, and at Stage II stations additional vapor recovery during refueling. The exposure of 20 customers was measured at both stations by collecting air samples from their breathing zone into charcoal tubes during refueling with 95-octane reformulated gasoline. Each sample represented two consecutive refuelings. The samples were analyzed in the laboratory by gas chromatography using mass-selective detection for vapor components. The Raid vapor pressure of gasoline was 70 kPa and an oxygen content 2 wt%. Oxygenated gasoline contained 7 percent methyl tert-butyl ether (MtBE) and 5 percent methyl tert-amyl ether (MtAE). The geometric mean concentrations of hydrocarbons (C3-C11) in the customers' breathing zone was 85 mg/m³ (range 2.5-531 mg/m³) at the Stage I service station and 18 mg/m³ (range < 0.2-129 mg/m³) at the Stage II service station. The geometric mean of the exposure of customers to MtBE during refueling at the Stage I service station was 15.3 mg/m³ (range 1.8-74 mg/m³), and at the Stage II service station 3.4 mg/m³ (range 0.2-16 mg/m³). The differences in exposure were statistically significant (p < 0 . 05). The mean refueling times were 57 seconds (range 23-207) at the Stage I and 66 seconds (range 18-120) at the Stage II station. The measurements were done on consecutive days at the various service stations. The temperature ranged from 10 to 17°C, and wind velocity was 2–4 m/s. The climatic conditions were very similar on the measurement days. Based on this study it was found that the Stage II vapor recovery system reduces gasoline emission considerably. The exposure level of customers at the Stage II station during refueling was circa 20–25 percent of the exposure at the Stage I service station when conditions were equal and no other confounding factors such as leaks or spills were present. [ABSTRACT FROM AUTHOR]

The purpose of the study was to assess the working conditions in hairdressing salons and the influence of work factors on the workers' health. Twenty randomly sampled hairdressing salons in the Helsinki, Finland, metropolitan area were selected for the study. The study was performed during winter 1994-1995; itincludeda survey of the hairdressing chemicals in use, the measurement of physical and chemicalworking conditions, and a self-administered questionnaire of the work environment and health of the workers. The air temperature varied between 16-25degreesC, air velocity 0.02-0.3 m/s, and relative humidity, 18-42 percent. The total dust concentration varied between 66-133 mu g/m3. The concentration of volatile organic compounds was 84-465 mu g/m3 and the peaks rose to 25-45 mg/m3. The highest concentration of ammonia detected was 3.5 mg/m3. The longterm concentrations of thioglycolates and persulfates were at their lowest below the detection limit, and at their highest 1.8 mu g/m3 for thioglycolates and 4.7 mu g/m3 for persulfates, respectively, and the peaks of persulfates, 30 mu g/m3. Hairdressing chemicals, awkward work postures, and repetitive movements were the most frequent causes of discomfort and for some had caused a work-related disease. Good general ventilation decreased the health complaints caused by hairdressing chemicals, but caused discomfort as a result of drafts. On average, the physical and chemical working conditions in the hairdressing salons were satisfactory compared with the Finnish criterion for indoor climate. However, the frequent high peak concentrations of chemicals during dyeing, bleaching, permanenting, and aerosolspraying stillpose a significant health problem. Although effective general ventilation alleviated the effects of the air pollutants, it could not completely solve the problem. Therefore, localexhaust ventilation is recommended at the mixing places for hairdressing chemicals and wherever they are applied to the hair. According to our results, already increasing the air exchange rate up to 5 to 7 times per hour during the high exposure jobs would improve the situation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to measure the exposure of road tanker drivers at work to gasoline and some of its components. The occupational hygiene measurements were made in two depots (one in northern Finland and the other in southern Finland) and in 11 service stations of a Finnish oil company during the loading and delivery of road tankers. Of the 21 measurements made, four were taken during top submerged loading of the road tankers and six during bottom loading at the depot. Eleven measurements were made during delivery at service stations. The duration of measurements varied from 10 to 44 min.The exposure of road tanker drivers to C3–C11 hydrocarbons of gasoline was under 300 mg m−3 during bottom loading measurements and during top loading exceeded 300 mg m−3 two measurements (50%).During delivery at service stations the exposure to C3–C11 hydrocarbons of gasoline exceeded 300 mg m−3 in four measurements (36%). The exposure of road tanker drivers during delivery depended mainly on the distance between working area and the emission point of discharging vapours from the tank, vents and wind direction.The mean exposures of road tanker drivers to benzene during loading and delivery were 1.1–18 mg m−3 in various situations. The mean exposures to n-hexane, to toluene and to xylene were 0.7–6.0, 1.4–11 and 0.8–4mg m−3, respectively. The exposures to methyl-tert-butyl ether were between 13 and 91 mg m−3. All measurements were made during the summer. However, the temperature varied between 4 and 22δC. [ABSTRACT FROM AUTHOR]