Initial start-up
Initial start-up means the first time a new or reconstructed source begins production. Initial start-up does not include operation solely for testing equipment. For purposes of subpart H of this part, initial start-up does not include subsequent start-ups (as defined in 63.161 of subpart H of this part) of process units (as defined in 63.161 of subpart H of this part) following malfunctions or process unit shutdowns.
Source
40 CFR § 63.191
Scoping language
For purposes of subpart H of this part