SKC Limited AirChek 3000 Deluxe Pump Step By Step Guide - Manual (Page 9)

www.skcltd.com 224-G1 Issue D Page 7
Dust Conventions
Dust, or more correctly aerosol, is split into
three size ranges, which have different effects
on the respiratory system of a human being,
as detailed in the diagram to the right. The
smaller the particle the deeper into the lungs it
can penetrate where it can settle onto the lining
and cause respiratory illness, for example, a
well known problem caused by respirable dust
is Silicosis in the coal mining industry.
Historically respirable dust has demanded
the most attention but in the last few years
particles of larger sizes have been investigated
for their effect on the upper respiratory tract
(throat, nose and mouth). Inhalable and
thoracic dust are a relatively recent addition.
It is important to note that inhalable dust
contains both thoracics and respirables, and
in the same way that thoracic dust contains
respirable particles.
The conventions are described in detail in the
European Standard EN481:1993 Workplace
atmospheres - Size fraction definitions for
measurement of airborne particles. The chart
Inhalable up to 100 microns
Thoracic up to 30 microns
Respirable up to 12 microns
ISO/CEN Aerosol Conventions
1 10
Aerodynamic diameter (µm - micron)
100 8 80 7 6 60 5 50 4 40 3 30 2 20
0
10
20
30
40
50
60
70
80
90
100
Per
centage of total airbor
ne
particles in convention
Inhalable convention
Thoracic convention
Respirable convention
The ISO/CEN Health Related Sampling Convention for Aerosol
(Refer to EN481:1993 for further details)
below (taken from EN481:1993) shows in
detail the particle size distributions for the
three conventions.