Using the laser photolysis/laser-induced fluorescence (LIF) "pump-and-probe" technique, the dynamics of H atom formation in the photodissociation of CH3-CF2Cl (HCFC-142b) after excitation at 193 nm-and the Lyman-alpha wavelength were studied under collision-free conditions in the gas-phase at room temperature. The H atoms produced were detected by (2p(2)P<--1s(2)S)-LIF using tunable narrow-band Lyman-alpha laser radiation (lambda(La)approximate to 121.6 nm) generated by resonant third-order sum-difference frequency conversion of pulsed dye laser radiation. In the VUV photodissociation experiments the Lyman-alpha laser radiation was used both to photodissociate the parent molecules and to detect the produced nascent H atoms via laser induced fluorescence. The following : quantum yields Phi(H) for H atom formation were determined by a photolytic calibration method : Phi(H)(193 nm)=(0.06+/-0.02) and Phi(H)(L-alpha,)=(0.53+/-0.12). From the measured H atom Doppler profiles the average H atom kinetic energy was determined to be ET(193 nm)=(51+/-10) kJ/mol and E-T(L-alpha)=(72+/-4) kJ/mol, respectively.