Respirable Silica Hazard Free Investment Powder

Investing in a Safer Working Environment


In a world first, GRS has carried out extensive research and development to be able to provide the industry with a product that is not a classified health hazard in relation to respirable crystalline silica, yet still provides the same high level of casting quality and usability as a traditional based investment powder.

In April 2019 we achieved our goal and have applied for a Patent to cover this new technology that enables the production of an Investment Powder that is classified as non-hazardous.

X-SIL technology investment powder can be used like for like in place of traditional investment powders in terms of usage procedures, water ratios, mixing equipment, furnaces and burnout cycles, casting machines, casting temperatures and downstream processes.



How does this compare with traditional silica based investment powder?

Typically, traditional silica based investment powder contains upto 10% Respirable Crystaline Silica. At this level it is classed as STOT RE 2 Hazard.

STOT stands for Specific Target Organ Toxicity which in this case is the respiratory system. In order to control this risk within the working environment, strict dust extraction and respiratory protection control measures must be put in place to comply with the work exposure limit within the country it is being used.

The work exposure limit for RCS in Europe is 0.1mg/m3 over an 8 hour time weighted average (8 hour shift) and in the USA it is 0.05mg/m3.  

Please check the applicableness of the work exposure limit to RCS in your location, if you require further information, please contact us. 

What about “dust suppressant” technology from the USA?

There are some products from the USA that utilise “Dust Suppressant” technology and claim to significantly reduce the airborne dust levels of traditional silica based investment powder products.

Independent testing of a product which utilises “Dust Suppressant” technology was carried out by the Institute of Occupational Medicine (IOM)- Edinburgh, UK which showed that this product contained 5.6% respirable crystalline silica according to Size Weighted Respirable Fraction (SWeRF) analysis of bulk materials.

This was compared by IOM to other products on the market of similar composition which do not utilise “Dust Suppressant” technology and the results showed respirable crystalline silica content in the range of 5.5 to 6.5%.

The IOM have independently tested a sample of our X-Sil product and confirmed there is no respirable crystalline silica present within the product. As with all refractory mineral dusts, traces of silica impurity can be present. 

Advantages of X-SIL

X-Sil has been developed to be able to cast all non-precious and precious alloys including High Palladium White Gold

It’s ease of use is one of it’s main advantages. GRS has engineered the product to at least match all cast surface finishes from our premium investment powder range without the need for any process or equipment changes.

Additionally, we understand the health of our customers workers is of paramount importance. By utilising X-Sil “Respirable Silica Hazard Free” investment powder technology you are protecting your workforce from potential exposure to harmful respirable silica

About Goodwin Refractory Services

Goodwin Refractory Services Ltd (GRS) and its sister companies are the global market leader in the manufacture of Investment Casting Powder for the jewellery industry in the world, producing over 65,000 tonnes worldwide per year. GRS is continually investing in R&D and understands the requirement of close customer relationships combined with a world class technical support network. Their complex manufacturing process is backed up by exhaustive raw material control testing and in-house quality control.


Please click on below to download the full mixing and burnout instructions