News and press releases

Marioff Receives Extended FM Approval for Fire Protecting Combustion Turbines and Machinery in Large Enclosures
25 August 2021

VANTAA, Finland, August 25, 2021 — Following a rigorous certification process, Marioff HI-FOG® high pressure water mist fire protection system with an electric pump unit has received an extended FM Approval to provide fire protection for combustion turbines and machinery with enclosures up to 2300m3

The approval nearly doubles the amount of space Marioff’s flexible fire protection solution can cover and gives the HI-FOG system added flexibility and makes it suitable for different types of turbine models and their configurations, as the spray heads can be installed both on the ceiling and at the midpoint of the turbine. FM Approvals is an international leader in third-party testing and certification services. Marioff, a leading developer of water mist fire protection technology, is a part of Carrier Global Corporation (NYSE: CARR), the leading global provider of healthy, safe and sustainable building and cold chain solutions. 

This new, extended approval is the result of long-term cooperation between gas turbine manufacturers and Marioff to gain internationally-recognized FM Approvals for using water mist fire protection to protect turbines.

Marioff’s previous FM Approval for combustion turbines and machinery, dated 2013, is for 1375m3 spaces. The extended FM Approval means a HI-FOG system can now be used to protect a wider range of heavy-duty gas turbines and large machinery spaces in enclosures that are almost a thousand cubic meters larger. The extended FM Approval also provides more flexible system installation criteria, as it allows to change the place of spray heads flexibly around obstacles without adding extra spray heads. Previously, obstructions like piping or walking platforms meant adding more spray heads – and more water.

The FM Approval was received after a development project between a gas turbine manufacturer, an insurer and Marioff.

“The most important starting point for the innovation process was to consider the practical requirements and limitations of modern heavy-duty gas turbines. Excellent teamwork and the turbine manufacturer’s insights for practical issues helped us shape the HI-FOG solution to fit the industry’s needs. We are very pleased that the new HI-FOG solution and FM Approval will enable us to better serve our customers in the power generation industry,” said Antti Hurme, Head of Business Development, Marioff.

The FM Approved HI-FOG system may also be installed in existing enclosures with gas turbines, oil tanks, electrical transformers and machinery, as well as  greenfield projects. For more information, visit


About Marioff

Marioff is a leading developer and innovator of high-pressure water mist fire protection, providing solutions worldwide under the HI-FOG brand. HI-FOG safely controls and suppresses fire using significantly less water than conventional sprinkler systems, reducing water damage, cleanup time and operational downtime. Marioff is a part of Carrier Global Corporation, the leading global provider of healthy, safe and sustainable building and cold chain solutions. For more information, visit


Marioff HI-FOG solutions are full-scale fire tested in test enclosure