Dust has always been a hazard and always will be. The key is controlling it on your sites.

allprep

20 Mar 2020

Dust has always been a hazard and always will be. The key is controlling it on your sites.

Dust has always been a hazard on construction sites. A large volume of dust is created when you cut, drill, grind or treat building materials such as concrete, stone and, timber. The larger particles are heavy and fall to the floor while the smaller particles can stay volatile in the air for a long time with the most harmful dust barely visible to the naked eye.


The smaller a particle is the deeper into the pulmonary system it penetrates. Respirable dust, the dust we inhale, is made up of particles smaller than 5 thousands of a millimetre. Because the particles are so small, they can penetrate into the deepest parts of the pulmonary system where the air moves too slowly to be able to breathe them out again. The lungs’ way of protecting themselves is to wrap the foreign particles in nodules of connective tissue, which, in time, leads to serious respiratory diseases. Some types of particles, such as silica and asbestos dust, cannot be broken down by the body and are also sharp, which is why they continue to cause damage long after they have become lodged in the lungs.

By having proper dust control measures onsite, you and your team can work safely without worrying about developing health problems due to being exposed to hazardous dust. The best protection is to remove the dust at the source and never allow it to reach the air. Ensure your tools, such as grinders, mixers, jackhammers, tile cutters, and drills have an effective suction casing or shroud to enclose the dust and allow it to be captured by an effective vacuum system.

Vacuums or Dust extractors are utilised to improve the work environment and eliminate unhealthy particles in the air. This places considerable demands on the dust extractor’s capacity to separate fine dust. To ensure that the dust extractor meets the requirements outlined in the relevant work environment provisions, it is classified in line with a standardised test. There is a detailed description of how the tests are performed to a vacuum and there are three classification levels and tests in accordance with IEC 60335.2.69 for each class, to verify the efficiencies of the machine unit and its filter elements.

L Class (light hazard) has an efficiency of >99% MAC suitable for separating dust with a limit value of occupational exposure of greater than 1mg/m³.

M Class (medium hazard) has an efficiency of >99% suitable for separating dust with a limit value of occupational exposure of greater than 0,1mg/m³.

H Class (High hazard) is the class with the most stringent criteria, stipulating a filtration efficiency of 99.995% for particles measuring from 0.1 to 5.0 μm. The machine is capable of maintaining a MAC (maximum workplace concentration) of <0.1 mg/m3.

 

Since anything containing Asbestos, Hexavalent Chromium and Silica is considered to be equally harmful to the human body, H class vacuum units seem to be the only viable choice. After all, there is silica in building materials used onsite daily, such as concrete, mortar, and bricks.

In most situations, a H Class Vacuum and dust shroud are not sufficient for capturing all of the dust particles created, in particular those that originate from other diffuse dust sources. In this case, it is also necessary to use an AirCube with your vacuum as a further measure to control dust onsite. The AirCube units capture airborne dust and draw them through a fine filter and H13 HEPA filter before returning clean air to the room. This separates dust particles even smaller than 0.3 micrometres resulting in a cleaner and safer working environment with close to zero dust. Most units also allow you to attach flexible ducting or an exhaust hose to create negative pressure in a sealed room, which is particularly useful in sensitive environments, such as during hospital refurbishments.

Finally, ensure you wear an approved respirator with a particulate filter as another measure to protect from airborne dust particles. People’s faces vary in size and shape therefore it’s important your respirator has been fit-tested. Fit-check regularly to ensure there is a tight-seal on your face and your respirator is providing sufficient protection based on the levels of air contamination onsite.

 

We’re here to help you control exposure to hazardous dust onsite -

Contact the team of dust destroyers at All Preparation Equipment to discuss your dust control solutions further on 1800 422 992.