McElwaine Technical Services Ltd was established in Co. Fermanagh, Northern Ireland in 1996. Their founding focus was integrity testing of process plant and equipment in the liquid food and dairy industries — and over three decades, they grew to become one of the most trusted operators in that sector across the UK and Republic of Ireland. Some of the best-known names in food and beverage choose MTS specifically for the consistency and rigour of their work.

In 2017, MTS entered the HOCl market. They commissioned their first production asset, completed the rigorous process of achieving Biocidal Products Regulations compliance, and launched Optizan® — a brand name drawn from the works of poet Emily Dickinson, referencing a visionary or a person of discernment. It reflects the precision behind their manufacturing process.


MTS has continued to invest in HOCl capability since, adding two further production assets. In 2026 they complete construction of a new dedicated manufacturing and administration facility in Lisnaskea, Co. Fermanagh — with a separate unit committed entirely to HOCl production and filling.

Crucially, MTS is the first company outside of North America to be accredited to the Green Seal global sustainability standard for their HOCl product Optizan® — a distinction that signals not just compliance, but genuine leadership in how HOCl is manufactured, bottled, and brought to market.