Table 1.

Summary of the influences of temperature (T), pressure (p), and humidity (H) of the resonance frequency f₀, the quality factor Q and the photoacoustic signal S. The sign before the slash defines how much the quantity is affected (+ – not, o – little, - – much), the second defines how easy a correction can be done (+ – easy, o – with effort, - – not possible), e.g. for bf-QEPAS, the temperature influence on the resonance frequency f₀ is little (o) and can easily be corrected (+).

	Bare fork			Off-beam
	Q	f0	S	Q	f0	S
T	+/n.a.	o/+	o/+	-/o	-/o	o/+
p	o/+	o/+	+/n.a.	o/+	o/+	+/n.a.
H	+/n.a.	+/n.a.	-/+	-/-	-/-	-/-