"Limited at all times" means that the NOx emissions of a source or device does not exceed the prescribed NOx emission limit over the averaging time specified in the applicable section of this part during the entire period of time that the source or device operates.
N.H. Admin. Code § Env-A 1302.24
(See Revision Note at chapter heading for Env-A 1300) #9803, eff 10-31-10