The organ of Notre-Dame is entirely covered with a layer of dust resulting from the combustion of several elements (wood of the frame, lead of the roof, to which could be added particles of the binder of the joints of stones, etc. .). The impact that this mixture can have on the material (pipes for example) according to its composition and the hygrometric variations that the great organ undergoes, and that it will undergo still from here to its cleaning remains for the moment unknown.Samples of pipes and dust were entrusted for analysis to the Historic Monuments Research Laboratory (LRMH) of the Culture Department.At the same time, and to accelerate the protection of the instrument, a protocol for decontamination, preservation, protection and cleaning measures has been proposed by Mr. Christian Lutz, authorized technical consultant of the Ministry of Culture for the great organ of Notre Dame de Paris, in liaison with the architect of historical monuments in charge of Notre-Dame, Mr. Philippe Villeneuve, who is particularly aware of the situation of the organs in the cathedral. The project management of these operations is under the responsibility of the regional department of cultural affairs of Ile-de-France.(Source: "Organ in France")