Measurements of minority‐carrier lifetimes (τ) in shallow‐junction GaAs LED’s under varying gas‐pressure conditions prior to and following γ irradiation indicate (1) τ is noticeably influenced by gaseous ambient and, (2) this influence is greaterfollowingirradiation than prior to irradiation. This dependence of τ upon surface phenomena indicates γ irradiation changes surface conditions considerably. Combination of both mechanisms on surface effects can be utilized to bring about noticeable improvement in diode speed of response using only modest dosages of nuclear irradiation (up to 60% improvement for only 13 Mrad). It is believed that γ irradiation affects trap density particularly, while changes in gas type and pressure change both trap density and electron capture cross sections at the surface through adsorption–desorption processes. This is believed to be the first time γ ray induced decrease of τ has been studied in different post‐irradiation gaseous environments.