Opacimeter and opacimeters tree to characterize the movement of smoke in fire tests

Opacimeter and opacimeter tree to characterize the movement of smoke in fire tests. The opacimeter comprises transmission means (1) comprising a laser emitter (2) configured to emit light; receiving means (3) comprising a phototransistor (4) configured to receive light emitted by the laser emitter (2); and means configured to obtain the opacity of the medium passing through the light emitted by the laser (2) and received by the phototransistor (4) processing. # tree opacimeter comprises a plurality of opacimeter arranged along a longitudinal guide , said shaft configured to measure the opacity of the medium in each of the heights that an opacimeter available.