N.Y. Comp. Codes R. & Regs. tit. 6, § 201-3.1 – Applicability.

(a) Except as provided in subdivisions (c) and (d) of this section, an emission source listed as an exempt or trivial activity in this Subpart is exempt from the registration and permitting provisions of Subparts 201-4, 201-5, and 201-6 of this Part. This does not mean that these activities are exempted from other applicable requirements or from applicable registration and/or permitting requirements of local air pollution control agencies.
(b) Unless otherwise provided for in this Chapter, emissions from exempt activities must be included in potential to emit calculations when determining whether a facility or emission source is subject to:
1. (1) title V facility permitting pursuant to Subpart 201-6 of this Part; and/or
2. (2) new source review pursuant to Part 231 of this Title.
(c) If the total potential to emit from one or more exempt activities at a facility exceeds, or causes the facility to exceed, the major facility threshold, as defined in Subpart 201-2 of this Part, those activities are no longer considered to be exempt from permitting. Such activities are still considered to be exceptions as described in Part 212 of this Title.
(d) If physical and/or operational restrictions are required to maintain the total potential to emit from one or more of the listed exempt activities below the title V applicability thresholds described in Subpart 201-6 of this Part, or new source review requirements described in Part 231 of this Title, the activities are not considered exempt for permitting purposes. Such activities are still considered to be exceptions as described in Part 212 of this Title.