Table 3.

Definition of Special Units on Nonratio Scales

u′	u	ν	f(x)	f-1(x)
1 C	1 K	1	x - 273.15	x + 273.15
1 F	1 K	5/9	x - 459.67	x + 459.67
pH	1 mol/L	1	-log10x	10-x
1 Np	1	1	ln x	ex
1 bel	1	1	log10x	10x
1 db(SPL)	1 Pa	2 × 10-5	20 · log10x	10x/20
1 db(mV)	1 mV	1	20 · log10x	10x/20
1 db(W)	1 W	1	10 · log10x	10x/10