One-photon laser excitation of PF(X(3)Sigma(-)) molecules generated in a discharge-flow reactor was used to prepare PF(A(3)Pi(0,1,2)) molecules in selected vibrational and spin-orbit levels. The radiative lifetimes, collisional relaxational mechanisms, and state-to-state rate constants for spin-orbit and vibrational relaxation were assigned in He and Ar bath gas for nu'=0-5 levels at 300 K. The radiative lifetimes, which are independent of the spin-orbit quantum number, Omega, decrease from 4.2 to 1.8 mus for nu'=0-5. The spin-orbit relaxation mechanisms in He and in Ar are independent of nu' level to within the experimental uncertainty. However, the actual rate constants for spin-orbit relaxation are different in He and Ar. In He the rate constant for DeltaOmega=-2 change are 2-fold larger than those for DeltaOmega=-1, whereas in Ar the order is reversed and the rate constants for DeltaOmega=-1 change are larger than the rate constant for DeltaOmega=-2 change. Furthermore, in Ar the rate constant for DeltaOmega=-1 transfer is much larger for 3Pi(1)-->(3)Pi(0) than for 3Pi(2)-->(3)Pi(1). Although the vibrational relaxation mechanisms in He and Ar have different degrees of involvement of the spin-orbit states, the overall vibrational deactivation rate constants are similar in He and Ar and both increase with vibrational level.