<p>Most plasma-based waste-treatment gasification systems employ arc plasma torches, in which the arc is usually stabilized either by a water vortex or by a swirling gas flow. Hybrid water–gas torches integrate both stabilization mechanisms. In current practice, argon is frequently selected as the stabilizing medium due to its strong arc-stabilizing capability; however, its presence in the produced synthesis gas is undesirable. This drawback motivates the search for alternative stabilizing gas compositions. Hydrogen has been proposed as a potential substitute for argon and may offer improved plasma-processing performance. In this study, we present thermophysical property calculations for argon–steam and hydrogen–steam plasmas, including enthalpy, electrical conductivity, thermal conductivity, and net emission coefficients. In addition, we introduce parameters derived from a simplified integral model of the arc column to characterize the influence of the stabilizing gas on arc-column behavior. The parameters were benchmarked against a more detailed one-dimensional numerical model of the central part of the plasma discharge. The results indicate that hydrogen increases the thermal conductivity and enthalpy of the plasma compared to argon, while the electrical conductivity is slightly larger for argon at relevant temperatures. The examined parameters suggest that hydrogen stabilization leads to higher arc voltages, although with increased heat losses to the torch walls. Relative to argon–steam, hydrogen–steam plasmas are expected to exhibit lower bulk temperatures while transporting higher enthalpy, which may translate into improved overall efficiency and supports the feasibility of hydrogen as an effective stabilizing gas for hybrid torches.</p>