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In this blog post will we explain the top 4 things to know about blast rooms and blast cleaning.

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Blast cleaning is a process commonly undertaken for the removal of surface contaminant, previously applied coatings, or corrosion. Ultimately it prepares a surface for a secondary treatment, such as the application of a protective or decorative coating.

In some cases, it is used to create a uniform finish on non-ferrous surfaces that require no protective coating, such as aluminium and stainless steel. However, in most cases the purpose of abrasive blasting is to achieve a level of cleanliness and a uniform surface roughness required by the coating to be applied.

Steel cleanliness is measured against a pictorial guide known as Swedish Standards or ISO 8501-1 and surface roughness is measured in the RA or RZ scale. Most coating data sheets will call for a defined surface cleanliness and roughness for correct adhesion of the coating to the prepared surface.

By propelling abrasive on an airstream onto a surface, both cleanliness and roughness can be achieved. Abrasive is typically held in a pressure vessel and forced onto an air stream, in turn propelled down an abrasive resistant hose and ejected at speeds up to 180mt per second from a blast nozzle.

By manipulating air pressure and abrasive type, a wide range of finishes is obtained. Whilst abrasive blasting is regularly undertaken “in the field” of preparing steel structures for the application of protective coating, it is also used in a more controlled environment commonly known as a blast room.

A blast room is an enclosure designed to be resistant to the process of abrasive blast cleaning. A blast room will contain the entire process, eliminating the risk to others from the escape of abrasive particulate and the dust generated by the process.

Typically, blasting rooms are been lined with abrasion resistant rubber and will be lit by purpose designed lighting systems that are able to resist the aggressive nature of abrasive blast cleaning.

A modern blast room will address the noise generated by blast cleaning, by incorporating noise suppressing materials in its construction. By adding a suitably designed dust extraction system to the booth, a level of visibility is provided to the operator that allows them to gauge their progress in achieving the desired finish and work safely.

When working out in the field it can be difficult to maintain the proper condition of abrasive for re-use, in a blast room this is not the case, as it allows the operator to use recyclable abrasives. This offers several advantages:

1. Cost savings: While recyclable abrasives may cost more initially, their durability allows them to be recycled and re-used multiple times, to varying degrees, based on the particular media.
2. Waste reduction: When blast cleaning is used for the removal of a previous coating it is not uncommon for that waste to be treated as contaminated. The use of this recyclable material in a blast room prevents the volume of waste associated with more friable abrasive that can’t be recycled.
3. Protects equipment: Recyclable media is kinder to the blast equipment and with the inclusion of abrasive recycling equipment that eliminates dust, oversized contamination and undersized media, the life of the various wear items, within an abrasive blasting system, are also extended.