An IR tip assembly includes a shroud having at least one feature that permits releasable attachment of a disposable cover fitted to a shroud. When the disposable cover is fitted to the shroud, at least one air gap is defined between the shroud and the disposable cover. An IR sensor disposed within the IR tip assembly is mechanically and thermally coupled to a heat sink. The at least one defined air gap creates a thermal isolation between the disposable cover and the disposed IR sensor. There can also be airflow through the at least one air gap. Apparatus and methods to create the airflow are described.