// WHAT IS LASER FUME EXTRACTION?
When a laser acts upon a substrate, there is a reaction in the form of a mark, cut or engraving. The material that is thermally decomposed during this reaction does not merely disappear; it is released into the surrounding atmosphere as laser fume or gas.
These are known as Laser Generated Air Contaminants or LGAC's.
Laser fume itself is essentially a mixture of all the chemicals that make up the original material being manufactured - it is the waste product of the lasering process.
In materials such as metal, ceramics and glass, much is released as microscopic particulate of the original, much like the dust produced when cutting wood, but on a micron scale.
However organic materials such as rubbers, powder coatings, and plastics produce far more complex fumes, known as Volatile Organic Compounds:
The VOC's are organic chemical compounds that have high enough vapour pressures under normal conditions to significantly vaporize and enter the atmosphere. The laser process catalyses the VOC gas as it heats and melts the material.
// LASER CUTTING PROCESS PRODUCING TOXIC FUMES
For example - Benzene is a VOC released when lasing certain rubbers, it can cause death, anaemia, low white blood cell count and is a known carcinogen.
Formaldehyde is a chemical used when producing polymers such as thermo set plastic or resin based materials. During thermal decomposition it is released as a carcinogen and is known to cause cancers, allergies and bring on asthmatic attacks.
These gases are generally produced in far larger quantities than air born particulates and must be addressed with closer attention, as they spread through the local environment very quickly.
This is particularly important with regards to PVC which releases extremely corrosive Hydrogen Chloride acid gas. This chemical has a maximum exposure limit of just 1 part per million and it is fundamental that this removed from the atmosphere efficiently and safely.
Almost all fumes produced through the use of laser falls under the umbrella of COSHH (control of substances hazardous to health)
This is covered further in our next section.
