Fast-response Self-Powered Neutron Detectors (SPNDs) demonstrated good performance in providing live-time, in-pile neutron flux measurements during transient operations at the Transient Reactor Test (TREAT) Facility at Idaho National Laboratory (INL) in the early 1990s. Two types of emitters for the fast-response SPNDs were tested?hafnium and gadolinium. Both types of SPNDs emitters generate electrical current which can be correlated to neutron flux. Gamma rays emitted from (n, ?) reactions in the emitter eject electrons by Compton scattering, which in turn induces the signal current. Current is also induced within the signal wire, thereby, necessitating a second compensation wire. The currents are subsequently measured using a pair of electrometers to provide time-resolved localized neutron flux measurement. These transient-response SPNDs have been reinserted into TREAT in 2018 to measure neutron flux levels and in-core power response during rapid reactivity insertion transients to support the recent TREAT resumption of operations. The objective of these experiments is to establish the instrumentation capability provided by fast-response SPNDs at INL to support transient irradiations. Testing of the SPNDs included the use of a gadolinium and a hafnium SPND in temperature limited and clipped reactivity insertion transients. The full-width half-maximum (FWHM) of the transient response measured from the SPNDs was compared with the TREAT ex-core neutron detectors as an initial step of analyzing the performance of the SPNDs and accompanying electronics. These SPNDs will be used as a benchmark for the development and fabrication of future SPNDs for deployment in transient irradiation tests.