40 CFR 63.9305 - What are my general requirements for complying with this subpart?
(a) You must be in compliance with the emission limitation that applies to you at all times, except during periods of startup, shutdown, or malfunction (SSM) of your control device or associated monitoring equipment.
(b) If you must comply with the emission limitation, you must operate and maintain your engine test cell/stand, air pollution control equipment, and monitoring equipment in a manner consistent with good air pollution control practices for minimizing emissions at all times.
(c) You must develop a written SSM plan (SSMP) for emission control devices and associated monitoring equipment according to the provisions in § 63.6(e)(3). The plan will apply only to emission control devices, and not to engine test cells/stands.