The reactor was also upgraded from the power level of 5 MW to 10 MW. The program was carried out to meet demands of higher neutron fluxes for experimental research purposes and the isotope production. The upgraded reactor was also made available to compensate for the decrease in neutron flux due to higher concentration of 238U in the LEU fuel as compared to the HEU fuel. The reactor was made critical on 31 October 1991 under the supervision of Dr. Ishfaq Ahmad and Dr. Iqbal Hussain Qureshi, and attained power level of 10 MW on 7 May 1992. The core configuration attained its equilibrium configuration in February 1995. The PARR-II Reactor is an indigenously designed and constructed reactor owned by the Pakistan Atomic Energy Commission. The PARR-II Reactor's design is similar to Miniature neutron source reactor (MNSR) and SLOWPOKE reactor. The reactor was indigenously designed by the PAEC as the chairman Munir Ahmad Khan and his team of engineers and scientists also led the construction of the reactor. The PARR-II Reactor had gone critical and began operating on 21 January 1974. The PARR-II Reactor is a tank-in-pool reactor with a rated power of 27–30 kW. Same as the first reactor, the reactor is designed to use the High Enrich Uranium (HEU) fuel. The HEU fuel use the ~90% 235U at a power level of 30 kW. The demineralised light water is used as a coolant moderator and the reactor core is reflected by metallic Be4. A PARR-II consists of a core reactor, control rod, and nuclear reflectors, and it is enclosed in a water-tight cylindrical Al13 alloy vessel. The nuclear reactor core is an under-moderated aray with 1H to 235U ratio of temperature of 20 °C and provides a strong Negative temperature coefficient and thermal volume coefficients of reactivity. The PAEC scientists and engineers also built and constructed the nuclear accelerator on 9 April 1989. The particle accelerator is heavily used to conduct research in nuclear technology. Unlike the PARR-I and PARR-II the "New Labs" is not subject to IAEA inspections. and is completely different from its parent reactors. It is a plutonium-fuel reprocessing plant and works as a pilot 94Pu reprocessing facility with a capability to use the ~7% 239Pu, to handle the isotopes and use the 86Kr emissions and radiation.