### Question
How is the "startup" defined?


### Answer
The term **startup** is defined in *40 CFR § 52.01* as follows -

> the setting in operation of a source for any purpose.

#### Citation:
  - *40 CFR § 52.01*
  - Heading: **Title 40—Protection of Environment > PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS > Subpart A—General Provisions > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)**

