Practicality vs. Passion: flammability considerations in a luxury yacht interior

Alexander Höfling explores the new technology enabling flame-retardant luxury onboard

For ships used in the passenger and charter sector, IMO requirements have been calling for long-term provisions for active and passive flame retardancy.

For those who don’t know, the International Maritime Organisation (IMO) is the United Nations agency responsible for the safety and security of ships and the prevention of marine pollution. It sets industry standards, in particular the rules and regulations of SOLAS (meaning “Safety Of Life At Sea”).

• International Conventions 11 e.g.  SOLAS, MARPOL, TONNAGE, COLREG
• International Codes 35 e.g.  FTP Code, FSS Code
• Resolutions & Circulars e.g.  Environmental (MEPC) & Safety (MSC)

However, the afore-mentioned rules and regulations for fire protection are not applicable for privately-used yachts with less than 13 passengers. Whether a boat qualifies depends upon:

1. Number of passengers and total number of persons on board

2. Use of the yacht: commercial or private

3. Selected Administration for registration and Classification

However, evidence repeatedly shows that fires still spread on these smaller yachts, especially those that do not use the materials certified by the FTP codes. Fires can break out easily and are often underestimated. But the fire itself is just one aspect. It is also very important that when parts of the interior start to smoke, they do not flood the ship with toxic gases.

Here is the test procedure provided by the FTP code (“fire test procedures”). The certified materials are either special plastics or non-combustible materials such as glass, stones or metals, as used on large yachts.

Part 1 defines incombustibility, part 5 examines low flammability and part 2 limits smoke and toxic gases. Only loose furniture may consist of flammable materials, as this could theoretically be thrown overboard in case of fire.

1. Non-combustible:
   is a material which neither burns nor gives off  flammable vapours in sufficient quantity for self-ignition when heated to approximately 750 C, this being determined in accordance with the Fire Test Procedures Code, Annex I part 1.
2. Low flame-spread:
   means that the surface thus described will adequately restrict the spread of flame, this being determined in accordance with the Fire Test Procedures Code, Annex I part 5.

3.  Smoke and Toxicity characteristics:
   are to be determined in accordance with the Fire Test Procedures Code, Annex I Part.

It goes without saying that one cannot always be prepared for every conceivable calamity. But what if, from an aesthetic and quality perspective, you do not want to use the certified materials for your yacht?

In the yachting sector, the comfort and luxury of organic materials such as real wood are reluctantly dispensed with. We are left with the question: How can fire protection be realised in an invisible manner as possible? Since luxury yachts are almost always furnished with traditional materials, it is nowadays necessary to resort to very complex procedures by specialists.

As there are very few compound-tested organic materials in the past that have been certified, classification authorities are also satisfied with the single layer certification of ships with PYC classification.

This involves each individual layer of the material structure being individually tested for flammability, smoke and toxicity, and certified accordingly.

But in present-day practice each material used is individually tested for these factors only. This method is also restricted since the certificate used for each individual layer may only be used up to a fixed thickness, and only in combination with the carrier material used in the test.  In other words, the final compound as used on board with interactions with the single layers are not tested on PYC vessels.

However, the regulations demand – at least for SOLAS Vessels – that testing specimen is to be as per the arrangement onboard.

Part 5 (low flame spread test) is required to comply with the requirements of Annex 1 Part 2 (smoke and toxicity test)

Detail A: Low flame spread and Smoke and toxicity requirements (FTP Code Annex 1 Part 2 and Part 5) 

In addition to paints, adhesives and especially the veneers used on board must be tested. Each veneer sheet is soaked front and back in a special saline solution. Only selected companies, such as Interior PROMAN and Leleu, offer certified veneers and are thus able to meet the single layer process. However, the process involves expensive and long transport routes and increases the risk of coloration corruption. The quality of the wood and its further development make increased demands on the testing.

Finally, a certificate is awarded, confirming that each of the layers used individually meets SOLAS’ requirements for flammability, smoke generation and toxic gas release when tested in laboratories on metals.

The expense may deter the customer and the companies involved and it is understandable that many would not take part in this testing voluntarily, as it would increase the cost of a new build enormously.

However, the Swiss development team from Nature Squared has an innovative approach to this problem. They have developed a composite system for wood surfaces.

In the past Nature Squared has successfully used similar processes to make special decorative organic surfaces flame retardant. This method is now also possible on wood veneers, without having to change their colouring by harmful procedures or damaging them at all. The process was adapted to the requirements of woods and implemented with proven methodology. Thus, any shipyard or joineries who are approved for this procedure can protect not only the vast majority of organic special surfaces, but also lacquered wood surfaces, without the need for any special treatment.

During development, the chemists looked to nature for solutions. They investigated how trees like the eucalyptus repeatedly survive bushfires, and looked at the sequoia tree, which uses fire to cast its seed and ensure its survival, for inspiration.

The composite system is based on the usual working method of joinery, but uses specially developed products. Almost all European and tropical wood species can be varnished, and it is not necessary to use special tools for the procedure.

To implement the system, the desired veneer is first applied with a special adhesive on a non-flammable substrate. Onto this veneer the specially created primer is applied. This, in combination with the other materials, creates the momentum for the desired flame retardancy.

Unlike the single layer variants, whose interferences pose a risk, the entire composite can fulfill the fire protection criteria here.

Finally, the desired surface gloss can be defined by varying the lacquer layers. Whether the surface ends up open pored, dull or shiny is entirely dependent on the client’s personal preferences.

The process is also faster than alternative solutions, because it eliminates the sending and handling of the veneers by a specialist.

The substances used comply with the REACH requirements and are therefore not harmful to health. The conducted work process is documented and can thus guarantee transparency. A correct usage of the components is therefore rapid and sufficient information is available at all times.

Unlike the single layer certificates, the composite tested certificate is the realistic assessment of the actual flammability and smoke and gas evolution of the installed product. All interactions of the product’s components are taken into account. This allows you to have confidence in the safety of the product and thus also in your own safety.

Frankly it is astonishing that this question arises in shipbuilding in the first place. In aviation, there are already clear requirements placed on the protection of individuals – without any exception, all commercially or privately used jets must be tested according to the fire protection specification. For personal protection, shipbuilding safety requirements should be demanded in the same way.

Creating wood surfaces using the composite system offers not only a lower cost, but also a less time-intensive way to protect themselves before a fire occurs. After all, low flammability can significantly extend the time window for a safe rescue, even on smaller private yachts. This means an increase in security could be created without sacrificing quality, comfort or a coherent interior design.