Based　on　the　hydrogen-helium　similarity　theory,　the　leakage　experiments　using　helium　instead　of　hydrogen　can　effectively　reduce　the　risk　of　hydrogen　deflagration,　but　the　experimental　results　show　that　there　is　a　large　difference　between　the　concentration　of　hydrogen　and　helium　in　initial　period　of　leakage　base　on　this　theory.　This　paper　focuses　on　leakage　experiments　under　turbulent　conditions　in　enclosed　spaces.　Based　on　the　hydrogen-helium　similarity　theory,　helium　is　used　to　replace　hydrogen　to　find　out　the　concentration　of　helium　at　multiple　leakage　speeds.　A　comparison　is　made　between　helium　concentration　values　and　hydrogen　concentration　values,　and　a　polynomial　correction　algorithm　is　used　to　shrink　the　difference.　The　results　show　that　this　correction　method　can　reduce　the　concentration　average　error　between　the　helium　and　the　hydrogen　from　14.06%　to　7.94%　for　the　Reynolds　number　range　of　3500–9500.　Therefore,　a　polynomial　fitting　algorithm　based　on　this　theory　can　improve　the　accuracy　of　experiment　using　helium　instead　of　hydrogen.　©　2024　Hydrogen　Energy　Publications　LLC