Research on the performance of personal protective equipment (PPE) for the Fire Service is challenged by the ability to repeatedly and feasibly test new designs, interventions and wear trials in realistic conditions that appropriately simulate end use environments. To support firefighter PPE research and firefighter PPE acclimation/training, a multidisciplinary team has developed a low cost, easily replicable approach for simulating conditions commonly encountered by firefighters operating on the interior of a residential structure fire. The testing enclosure can be used with either stationary mannequins or firefighters conducting typical fireground activities, providing a method to study a wide range of PPE and physiological studies as well as training activities that may support developing new technologies and standardized testing opportunities. Environmental gas concentrations and firefighters' local temperatures were measured during trials and compared to data collected from simulated fireground activities and fireground responses with good agreement.