Let’s be direct: what is silica gel, and how do the words “carcinogenic”, “cobalt blue”, and “non-cobalt” relate to it?
Silica Gel is SiO2. Silica gel has indicating properties, such as blue-to-pink, orange-to-white, and orange-to-green. Despite these indicating properties, the base product remains SiO2, which is silicon dioxide.
Silicon dioxide is the indicator that determines what the start and end colours will be. Here is a rough guide of three of the well-known indicating silica gels on the market and the typical indicator that is used in each version:
However, the organisation that conducted this research has since switched to utilising non-cobalt based silica gel, particularly orange-to-green silica gel, which has the methyl violet as the indicator. The decision was based on the fact that the orange-to-green silica gel, also known as e-Gel, is more environmentally friendly and is non-cobalt based, therefore classified as non-carcinogenic.
Meanwhile, a large power company was faced with a supply chain scarcity for silica gel, and so approached a different supplier than their usual. The new supplier’s response was to provide the power company with blue-to-pink indicating silica gel, which was unacceptable for the power company’s needs. The alternative provided by the new supplier was orange-to-white silica gel; the power company put the silica gel to trial use for twelve weeks.
After this trial period, the power company’s substation maintainer contacted the power company and complained about the new orange-to-white gel discolouring after only three months in the field.
With professional trust between the power company and the supplier now damaged, the supplier offered orange-to-green silica gel to the power company as a last option. The orange-to-green silica gel then underwent a scrutinising process and trial, where it performed extremely satisfactorily for the power company’s needs.
The orange-to-green silica gel, or the e-Gel, has since then become a favourite for electrical departments for its strong colour indicating curve, its coping well in harsh weather conditions and high-UV areas, and its being non-carcinogenic and more environmentally-friendly qualities.
For more information, visit omnituff.com/egel-silica-gel/.