This modifier type is used to indicate after hours time units for services provided to patients in active treatment hospitals, AACCs, UCCs, nursing homes and auxiliary hospitals. This modifier is payable in 15 minute blocks to a maximum of 4 per hour, per physician. It is to be billed beginning at the time of contact with the patient and may only be claimed for direct patient care time related to the provision of an insured service. The after-hours time premium units may not be claimed for stand by time, e.g. time spent waiting for results of diagnostic tests. In the event that one 15 minute period covers two time periods, the modifier claimed will be based on the time period where the majority of the 15 minute period was spent. In the event that the time spent with the patient covers more than one time period, additional SURT modifiers may be claimed, each according to the time spent with the patient in that particular time period.