Table 3.

Multi‐gamma regression for predicting the concentration of TVOCs and acetone (ppm)

Factors	Target VOCs			Acetone
	β	SE	P‐value	β	SE	P‐value
No. of customers in the salon				1.05	1.01	<.001
No. of serviced customers	1.19	1.05	<0.001	1.49	1.05	<.001
Concentration of CO2	1.001	1.002	<0.001	1.001	1.001	<.001
General ventilation	1.44	2.00	*NS
Air conditioner used				0.25	1.45	<.001
Volume of salon	1.002	1.002	*NS

Abbreviation: VOCs, Volatile organic compounds; β, Regression coefficient; SE, Standard error; *NS, Not significant.