A pulsed discharge lamp containing Hg vapor suitable for kinetic spectroscopy in the nanosecond time range is described. The spectral output is practically the same as that from a conventional low pressure mercury resoance lamp. The light intensity of the 253.7 nm resonance line is about 1010photon/pulse. The width of light pulses is about 10 ns, except at 253.7 nm, which pulse width is about 40 ns. The repetition rate is 5–10 kHz. Quenching rates of Hg(3P1) atoms by H2, C2H4, CO, and NH3are obtained by measuring decay rates of the 253.7 nm resonance line.