Consequent　to　abandoning　the　use　of　halon　in　total　flooding　gas　protection　systems,　clean　agents　are　used　for　fire　control.　It　is　difficult　to　carry　out　so　many　physical　experiments　on　assessing　their　performance.　Numerical　modeling　is　an　effective　tool　and　computational　fluid　dynamics　(CFD)　is　a　good　method　for　studying　the　interaction　with　the　fire-induced　flow.　Thermal　radiation　is　a　key　point　in　modeling　such　process　and　the　importance　of　it　will　be　discussed　in　this　paper.