Techniques of digital simulation have been used to model the reaction zone yielding chemiluminescence in conventional double or triple potential step experiments. Each simulation describes the steady state achieved within a fixed volume into which the reactant radical ions are injected at a constant rate. Thus each simulation depicts a single point along the luminescence decay curve. Other points are examined via simulations involving different rates of reactant injection. Radical ion annihilation, triplet‐triplet annihilation, first‐order triplet decay, and triplet quenching by the radical ions are all modeled directly. Problems associated with the simulation of a steady state are discussed in detail. The results of simulations for various sets of realistic rate parameters are compared with the predictions of a simplified treatment of the reaction zone as a homogeneous region of constant width. The impact of quenching by radical ions is evaluated quantitatively for the first time. The results show that one can usually expect triplet lifetimes to be controlled by these species at times early in the light pulse. The importance of this conclusion to the usual interpretation of magnetic effects is discussed.