What size particle is considered respirable?

Respirable fraction – defined as the mass fraction of particles that can reach the alveoli. The median value of the distribution of particle sizes in this category is 4.25 µm with a GSD of 1.5. It has been shown that 50 % of the particles with an aerodynamic diameter of 4 µm will be in the respirable fraction.

What is a respirable particle?

What are Respirable Particulates? A collective group of fine solid particles, aerosols, mist, smoke, dust, fibers and fumes are called Respirable particulates. The main indoor respirable particulates are ETS and fibers.

What is the definition of respirable dust?

Respirable dust sampling is a process of measuring contaminants in the volume of air at a given workplace that can be inhaled by workers. Various dust sampling methods are used to identify the volume of dust particles and chemical vapors to make sure the health of workers is not at stake.

What is the criteria for fibers to be considered respirable particulate matter?

Recently, the American Conference of Governmental Industrial Hygienists (ACGIH) has defined respirable fibers as possessing a diameter <3. µm, length ≥5 µm, and an aspect ratio of ≥3:1 (ACGIH 2001). The term respirable fiber in this chapter refers to fibers possessing diameters of <3. µm, unless otherwise noted.

What is respirable fraction?

Respirable particulate fraction is that fraction of inhaled airborne particles that can penetrate beyond the terminal bronchioles into the gas-exchange region of the lungs.

What size dust is respirable?

Relative to total airborne particles, the particle size having 50% penetration for the thoracic and respirable fractions are 10 μm and 4.0 μm (all particle sizes are aerodynamic diameter unless expressed otherwise), respectively [2,3]. These criteria were specifically developed for workplace atmospheres.

What is meant by respirable?

: fit for breathing also : capable of being taken in by breathing respirable particles of ash.

How many microns is respirable dust?

Respirable Dust A hazardous particulate size less than 5 microns. Particle sizes of 2.5 micron (PM2.5) are often used in USA.

What is respirable particulate mass?

Respirable fraction – the mass fraction of inhaled particles penetrating to the unciliated airways. These criteria were based on exposure of a respiratory tract region (based on particle penetration into that region), not particle deposition in a respiratory tract region.