Where both thermal and fire insulation are required for cold stores, the cost of MacGREGOR's new fire-resistant Pyro-Foam panelling package offers more cost-saving benefits than conventional solutions

Pyro-Foam is a new fire-resistant foam developed by MacGREGOR's Passenger Ship division for the insulation of prefabricated panelling. While the new foam has been developed specially for panels for provisions stores and walk-in refrigerators, it is also available in a range of fire-resistant doors intended for use in cold stores.

Pyro-Foam is an environment-friendly modified phenolic foam which does not contain any CFCs and has an ODP (ozone depletion potential) of zero. It has a fine cell structure which results in a consistent thermal conductivity in the range 0.0185-0.02W/m.K at 10°C. During the foam's lifetime, this thermal conductivity remains unchanged.

Pyro-Foam is inherently fire resistant so separate fire retardants are not required. Tests with Pyro-Foam show that a foam-filled 100mm-thick panel has more than 60 minutes of fire resistance.

Humidity resistant

Antonio Ferrando, cold stores product expert in MacGREGOR's Passenger Ship division, points out that the main advantages of the new Pyro-Foam are not only its high levels of fire resistance and thermal insulation, but also its ability to resist humidity. Other materials on the market, such as rockwool, may offer fire resistance and thermal insulation, but they also absorb humidity.

By using panels filled with Pyro-Foam it is possible to reduce the prospect of flash-over and the spread of fire, as phenolic foam has a low burning rate and a low rate of heat generation. The amount of smoke generated is also minimal, particularly compared with traditional polyurethane and polyisocyanurate based foams. In the event of a fire, visibility is increased, making evacuation safer. Minimal amounts of toxic gas are emitted making not only evacuation safer, but also fire-fighting.

The Pyro-Foam-filled prefabricated panels are constructed in compliance with USPHS requirements. Visible surfaces are covered in stainless steel with a 0.6-0.8mm thickness, and galvanised steel or polyester-coated galvanised steel of the same thickness is used for the hidden surfaces. The foam is injected under pressure between the metal skins and forms a chemical bond.

Modular panels up to 6m in length and 1.2m wide can be constructed. Camlock mechanical locking fasteners have been incorporated to help make installation for the shipyard faster, cleaner and more efficient.

Mr Ferrando highlights that there are also cost advantages to be gained by choosing the Pyro-Foam system. While the cost for the new Pyro-Foam panel itself is higher than that for a polyurethane panel, where both thermal insulation and fire insulation are required the cost for the Pyro-Foam package is much lower than conventional solutions.

Benefits of Pyro-Foam panels:

• A60 equivalent fire-resistant panels

• overall weight savings: weight of panels reduced due to dispensing with the surrounding steel bulkheads

• overall cost savings: no need for surrounding steel bulkheads, no need for penetrations above the cold stores, no need for door steel cutting

• overall space savings: extra floor area gained from dispensing with surrounding steel bulkheads can be used to increase size of cold store

• overall installation time savings: no increase of installation time for Pyro-Foam panels, no installation of steel bulkheads, no penetrations, no door steel cutting and stainless steel lining

• environment-friendly: no CFCs, zero level ODP, minimal smoke and toxicity levels.