Welding fumes are composed of many different substances, many of which are in the nanoparticle range. Yet, how large are such nanoparticles?
In dimensions, the distribution looks as follows:
1 millimeter = 1,000 micrometers
1 micrometer / 1 µm = 1,000 nanometers
The following graphic is an illustration example: A fine dust particle has the same ratio to the football as the football has to the earth.
Particles in the micrometer range can not be seen with the naked eye. And this is what makes those finest particles so dangerous - they are practically an invisible Toxin.
Depending on the size of the particles, dust is divided into individual so-called "fractions". Coarse dust means particle sizes of 10 µm and larger. Particulate matter is referred to as fine dust in smaller particle sizes down to eta 0.01 µm. They are already in the area of ultra free dust and gas molecules.
Particles of a size of less than 1 µm are a particular danger as these can enter the avioli; that is they can reach the inside of the lungs and air sacs. Ultrafine particles pass through cell membranes. Into the bloodstream and all the way to the brain. There they cause brain and nerve damage.
In welding fumes, almost all particles are smaller than 1 µm. Ultra-fine particles are also present in significant quantities. Suction of these substances is therefore essential.
>> to 1. Welding fumes - What are they?
>> to 2. Composition of welding fumes
>> to 4. Physical effects by absorbing pollutants in welding fumes