Low-volume notification applies to new chemicals ubstances to be manufactured or imported at less than 10 tons/year,and small-volume notification applies to those at less than 1 ton/year.
The 2017 revision of CSCL, which took effect in 2019, introduced a new concept called “environmental release volume” to replace the manufacture or import volume of a substance as a confirmation criterion with regard to small-volume and low-volume notification.