Statistical analysis
The exposure data were analysed by using the Statistical Package for Social Sciences (SPSS). The results
are presented as descriptive statistics.
Comparisons of the log-values of the concentrations of ammonia and ethanol in different
groups were performed by the use of Student's /-test
(deviation from a log-normal distributions was tested
by Shapino Wilks test). The different groups were
the salons with ventilation and the salons without
ventilation.