No one can even tell me what a hot room is?
Not sure if this is what they mean or not, but generally a 'Hot room' is a room kept between 30 and 40c and is used to dry clothing and equipment. Keep temperature sensitive equipment and samples stable.
They are commonly employed on construction and environmental research sites. And by the electrical trade for cable stablization during winter installations. (The insolation on cables gets brittle in temperatures less the -20c..... and the last thing you want to do is crack the insulation on cables that cost $1m/km!