- Typical capacity
- Varies significantly; units of this type commonly range from 500 litres to several thousand litres.
- Construction material
- Typically 316L stainless steel for all wetted parts, with a high-grade internal surface finish (e.g., electropolished) to prevent microbial growth.
- Temperature control
- Units are commonly designed to maintain WFI at elevated temperatures (e.g., 80-85°C) to inhibit microbial proliferation, or at ambient with continuous recirculation and sanitisation capabilities.
- Insulation
- Commonly features external insulation and cladding, often in 304 stainless steel, to minimise heat loss and protect personnel.
- Agitation/Recirculation
- Often includes a spray ball or recirculation loop for effective cleaning and to maintain water quality throughout the vessel.
- Instrumentation
- Typically fitted with temperature sensors, level sensors, and pressure relief valves. May include conductivity and TOC (Total Organic Carbon) monitoring points.
- Certifications
- Units for WFI storage are typically designed and built to meet cGMP requirements and often comply with ASME BPE standards.