The difference is explained in D.P.C.M. of 12 March 2002.
Title I " Fuel and technologic characteristics of combustion plants for industrial use" See art 1 Application field and Art. 5 Plant requisites.
Title II " Fuel and technologic characteristics of combustion plants for civil use" See art 7 .
Essentially the plants for productive process with thermic rated output for single fireplace equal or higher than 6MW have to be equipped with an analyzer to continuously measure and record the free oxygen and the carbon monoxide and with a temperature detector in the confluent gases.
For civil use plants at point 2 art.7 it is specified that they have to be equipped with an analyzer to continuously measure and record free oxygen and carbon monoxide and with a temperature detector in the confluent gases in order to optimize the combustion yield with total thermic rated output equal or higher than 1,5 MW .