Nowadays, formaldehyde has become a ubiquitous element in the environment, which is also being used in the manufacture of phenolic resin by chemical reaction of phenol-formaldehyde. These processes are related to high levels of formaldehyde contamination and, consequently, to a dangerous risk to human health. To which must consider that at a global level labor and safety regulations do not yet include this gas as a human carcinogen. In this research, several tests have applied to the reactor, such that its thermal signals plus formaldehyde pollution around the environment of the reactor have been used for a successful identification by a mathematical procedure using the Laguerre functions. Another goal is to find the thermal condition that triggers formaldehyde pollution. Finally has been to find a model endowed enough capability to will be using it in pollution control tasks in such industrial facilities.