With thanks to Mr Seiji Uehara for this video which clearly demonstrates the benefits of using an ultrasonic liquid level indicator rather than using radioactive level indicator.
The Portalevel® IS proudly boasts Ex Veritas approval to Zone 1, II 2 G Ex ib IIA T4 Gb standard, the only ultrasonic liquid level indicator of its kind with such rating. With this approval the Portalevel® IS is explosion proof instrumentation. The unit is ideal for environments with gas, vapours and mists (IECEx Zone 1) such as LNG Tankers, Offshore Platforms with flammable gases, Breweries, Chemical plants, Petrochemical and Hazardous material storage facilities plus many more.
EXTRACT: Discrepancies between standards for marine and land based fixed gaseous fire extinguishing systems. The findings of MAIB report no 16/2018 highlighted that there were some significant differences between the use and servicing of Marine CO2 fixed gaseous fire extinguishing systems and essentially similar land based systems.