Abstract: The composition of flue gas generated in a thermal process, especially in the combustion of bio fuel or refuse-derived fuel, is monitored by measuring the quantity of particles belonging to certain size categories in at least one point along the flow path of the flue gas. Such particle size categories are chosen as objects of the measurement, in which the particles are known to consist mainly of alkali chlorides.

Abstract: The invention relates to a measuring device for measuring aerosols, which measuring device comprises detection means (13), means (41) for conveying a signal from the detection means (13), a first insulation (43), a second insulation (44), and a supporting means (42). The first insulation (43) insulates the medium (41) from the supporting means (42), and the second insulation (44) insulates the detection means (13) from the supporting means (42). Also, the second insulation (44) is designed in such a way that it positions the detection means (13) in a predetermined location.

Abstract: An impactor, a frame part for an impactor, a part to be used in an impactor, and a method for processing elements belonging to the impactor. Different elements belonging to different stages of the impactor are coupled to each other with a connecting element in such a way that they can be inserted in the frame part of the impactor, removed from it, or processed, as a single unit.

Abstract: The invention relates to an impactor, a frame part for an impactor, a part to be used in an impactor, and a method for processing elements belonging to the impactor. According to the invention, different elements belonging to different stages of the impactor are coupled to each other by means of a connecting element in such a way that they can be inserted in the frame part of the impactor, removed from it, or processed, as a single unit.

Abstract: The invention relates to a measuring device for measuring aerosols, which measuring device comprises detection means (13), means (41) for conveying a signal from the detection means (13), a first insulation (43), a second second insulation (44), and a supporting means (42). The first insulation (43) insulates the medium (41) from the supporting means (42), and the second insulation (44) insulates the detection means (13) from the supporting means (42). Also, the second insulation (44) is designed in such a way that it positions the detection means (13) in a predetermined location.