Wall Radiative Heat Loss Formula

\begin{equation}\label{eq:wall-qrad} Q_\text{rad} = \varepsilon \sigma A (T_s^4 - T_a^4)\end{equation}

Symbols

\(Q_\text{rad}\)	Radiative heat loss \([\unit{ \btu\per\hour}]\)
\(\sigma\)	Stefan-Boltzmann constant \([\unit{ \btu\per\hour\foot\squared\degreeRankine\tothe{4}}]\)
\(\varepsilon\)	Surface emissivity \([\unit{ \unitless}]\)
\(A\)	Surface area \([\unit{ \foot\squared}]\)
\(T_s\)	Surface temperature \([\unit{ \degreeRankine}]\)
\(T_a\)	Ambient temperature \([\unit{ \degreeRankine}]\)