This paper describes a thermal sensor developed for use in the fingers of the PyroHands Fire Test System. The PyroHands Fire Test System measures the thermal protective performance of gloves in laboratory controlled flash fire exposures. The development of the finger sensor presented several challenges; the first was that it required that a small thermal sensor fit into the finger of an anthropometrically designed hand. It was also important to ensure that the thermal sensor accurately measured heat flux incident on the finger. This required showing that the unidirectional heat flux measured by the sensor was unaffected by heat impinging on the sides and back of the finger. An experimental study was conducted in order to investigate the effects of lateral heating on sensor operation. Additional verification of the thermal sensor was provided via the use of computer-aided design models to predict the temperature rise beneath gloves during PyroHands tests.