For further informations and contact persons click the link below: Particle and fiber analysis | DMT Group (DMT-Group.com) Determination of the inhalable, thoracic, and respirable dust fractions according to DIN 481 DMT conducts investigations of dusting indicators using three variants with a rotating drum. The basic structure and processes are analogous in all three methods. A sample of the bulk material is set in motion within a drum of diameter d and at a rotational speed of n for a defined time t using entrainment plates. Airborne particles from the cascading bulk material are discharged from the drum by an axial imposed air flow V̇. The discharged particles are quantified in the subsequent analysis, and optionally, the particle fractions are determined. The process parameters d, n, t, and V̇ are specified in the respective standards and are specific to the standard, as is the particular analysis method. d = 14 cm n = 30 min -1 t = 300 s V̇ = 20 l/min The discharged laden air flow passes through a horizontally oriented glass section, which fundamentally serves as a coarse separator or sifter. Subsequently, the finer particles are collected on an absolute filter and quantified gravimetrically. This results in a dimensionless parameter that relates the collected dust quantity on the filter to the initially used 100 g sample quantity. Figure I: Test rig DIN 55992-1

For further informations click the link below: Partikel- und Faseranalytik | DMT GROUP (dmt-group.com) d = 30 cm n = 4 min -1 t = 60 s V̇ = 38 l/min Initially, 35 cm3 of sample is used. The discharged particles are collected using three particle size-selective metal foams and an absolute filter. The first two metal foams are identical. The duplication is normatively anchored and serves the purpose of manageability. Within this standard, the following table can be found for classifying the obtained results. Classes: very low low moderate high Dustiness of inhalable dust, w I,A mg kg -1 300 to 650 > 650 to 3000 > 3000 Dustiness of thoracic dust, w T,A mg kg -1 80 to 300 > 300 to 1000 > 1000 Dustiness of respirable dust, w R,A mg kg -1 10 to 60 > 60 to 210 > 210 Figure 1: Basis for evaluating the results. Taken from DIN EN 15051-2 Air flow Inlet unit (protective filter) Dust generation unit - rotating drum Outlet unit / sampling system (two particle size-selective filter foams and an absolute filter) Roller Inline mass flow meter Control valve Vacuum pump Timer Drive motor

For further informations click the link below: particle and fiber analytics | DMT Group (DMT-Group.com) Determination of the inhalable, thoracic, and respirable dust fractions according to DIN 481 DMT conducts investigations of dusting indicators using three variants with a rotating drum. The basic structure and processes are analogous in all three methods. A sample of the bulk material is set in motion within a drum of diameter d and at a rotational speed of n for a defined time t using entrainment plates. Airborne particles from the cascading bulk material are discharged from the drum by an axial imposed air flow V̇. The discharged particles are quantified in the subsequent analysis, and optionally, the particle fractions are determined. The process parameters d, n, t, and V̇ are specified in the respective standards and are specific to the standard, as is the particular analysis method. d = 14 cm n = 30 min -1 t = 300 s V̇ Trommel = 20 l/min The discharged loaded air flow is channelled via a probe into a seven-stage cascade impactor. A continuous curve is generated numerically from the particle size base points determined in this way as a particle size distribution of the aerodynamic diameter of the airborne particles. For the evaluation of the impactor, the material density is determined using helium pycnometry before the actual test (Micromeritics Accu Pyk II; included in the price; result sheet is provided to the customer). Figure 4: Exemplary illustration from the modified Heubach Method 2 Figure II: Structure and diagram of the modified Heubach Method 2 as a variant of DIN 55992-1 Legend: Dust generation unit Detail: Sampling current + bypass current to obtain 40 l/min in total for (3) Seven stage cascade impactor Motor (30 rpm) Timer (300 s – 5 min) Vacuum pump Rotameter Three-way-valve