MRS-25 Weather Shield

MRS-25 Weather Shield

Maxwell MRS-25 Weather Shield (EFR Rim Seal) 

Our MRS-25 Weather Shield may be installed over the primary seal to protect it from deterioration caused by debris and exposure to the elements.

Though the covering standards do not accept the installation of a weather shield as equivalent to a secondary seal, there are a large number of existing tanks covered by this configuration.

Typically, a weather shield is an arrangement of overlapping thin metal sheets pivoted from the floating roof to ride against the tank wall. The weather shields, by the nature of its design, is not an effective vapor barrier. For this reason, it differs from the secondary seal. Although the two devices are conceptually similar in design, they are designed for and serve different purposes.


Maxwell Floating Roof Rim Seals are custom designed to each individual tank within the requirements of API 650/653, BS 2654, EN-14.015 and EEMUA-159.

Maxwell Continental Tank Serv Engineering has combined over 20 years’ experiences from the past with their research and development, through which it has produced increasingly innovative products for reducing above ground storage tank (AST) emissions.

And it’s not just about the new and interesting, when old technologies and products are to be revitalised or re-used it always can be reviewed and when needed altered to be made more efficient.




The most commonly used Maxwell Vapor Mounted Seals or vapour mounted seals either used as a single or combined configuration are:

• MRS-20P Primary Compression Plate Seal


All Maxwell EFR Rim Seals can be combined with;

• MRS-20S Secondary Compression Plate Seal

• MRS-25 Weather Shield


Finally, when the local requirements are pushing local terminals or refineries to add a tertiare or tertiary or triple rim seal, on request these extra rim seals can be provided by Maxwell.