# How does the use of inert gas in fluorination of saturated aliphatic hydrocarbons make it less violent?

While studying alkanes, I found this written in my book:

Fluoridation can be achieved without violence when alkane is treated with fluorine diluted with an inert gas, or by the action of inorganic fluorides like $\ce{AsF3}$, $\ce{SbF3}$, $\ce{AgF}$, $\ce{HgF2}$, $\ce{Hg2F2}$, etc., or by use of bromo or iodo derivatives.

The picture is given below for clarification:

Inert gases are chemically inactive, except xenon and radon, which are radioactive and may form some compounds.

How do the non-radioactive inert gases help in reducing the violence of fluorination? If I put a certain volume of fluorine and an alkane in a jar for reaction, then even if inert gases are present, they won't react. What is their role?