The explosion took place at 3:05 PM when the technician Shakeel along with his helper Sikander was servicing the split air-conditioner at the Biotechnology Centre, a senior police officer said.
The impact of the explosion was such that Shakeel died on the spot while Sikander and four women staffers suffered serious injuries from the splinters of the glass windows at the centre, police said.
The injured have been admitted to AIIMS.