Best fire resistant polymers

[Markusik]

Could you please share some insights on the best fire resistant polymers for building a glass boat (cruising sail catamaran) using vacuum infusion? Things like cost, ease of use, material safety.

Below the waterline I’d avoid polyesters, but would consider them for furniture etc.

Thanks!

 

[ondarvr]

FR resins tend to cost a great deal more and can be hard to find, there's not a huge demand for them, although the Coast Guard does require them for some applications.

Depending on the code/spec it meets there isn't much value in using them, the common ones have an ingredient that suppresses the flame, but the smoke is more toxic than regular polyester. The more expensive low smoke versions are very difficult to use.

Just about every resin manufacturer has one.

 

[KD8NPB]

Ashland MODAR / HETRON is what you need. They primarily rely on ATH to suppress fire. Alumina trihydrate flashes in to steam when exposed to high temperatures.

Bromine is also popular, it acts as a fire suppressant by suffocating the flames, but is also caustic to your lungs.

Unless you're building a commercial vessel, it's complete overkill.

Keep in mind too, these are typically filled resins.

 

[Markusik]

The purpose of the fire resistance would be to protect property and lives, particularly my family’s. A certain amount of money would seem worth decreasing the possibility of us being cooked alive, stranded overboard, or losing our possessions. I confess there is a lot about boat building I don’t know. The boat (currently in pre-design phase) will use petrol outboards for auxiliary propulsion. I realize that explosion is a concern with petrol relative to diesel, but the fuel tanks would be vented to the bridgedeck tunnel with the outboards themselves in bridgedeck wells. I know boats don’t regularly burst into flames, but it is a nightmare scenario.

Seeing as this will likely be a one-off, maybe I should build in aluminum instead.

Thanks, ondarvr and KD8NPB, I appreciate your advice.

 

[BlueBell]

Fire at sea is bad, as bad , or worse, than sinking.
A fire plan can hugely reduce the danger.
Regular drills will reduce it further.
And prevention can nearly eliminate it all together.

"Don't be scared, be prepared."

 

[DCockey]

The boat (currently in pre-design phase) will use petrol outboards for auxiliary propulsion.

My guess is fires aboard boats rarely if ever originate in the laminate. How intense does a fire have to be before the laminate burns?

 

[ondarvr]

I've used these also, they tend to be a bit more user friendly than most others. You won't be able to infuse with a filled system (ATH added) though, so you may not get the absolute best FR properties.

https://www.aoc-resins.com/pdf/lit_AOC_FireRetardantBrochure_WEB.pdf

 

[KD8NPB]

The purpose of the fire resistance would be to protect property and lives, particularly my family’s. A certain amount of money would seem worth decreasing the possibility of us being cooked alive, stranded overboard, or losing our possessions. I confess there is a lot about boat building I don’t know. The boat (currently in pre-design phase) will use petrol outboards for auxiliary propulsion. I realize that explosion is a concern with petrol relative to diesel, but the fuel tanks would be vented to the bridgedeck tunnel with the outboards themselves in bridgedeck wells. I know boats don’t regularly burst into flames, but it is a nightmare scenario.

Seeing as this will likely be a one-off, maybe I should build in aluminum instead.

Thanks, ondarvr and KD8NPB, I appreciate your advice.

Use a light vinylester for primary construction.
Metal cladding or phenolic resin around the engine room with nomex coring to insulate and slow flame spread.
Buy a liferaft.

 

[TeddyDiver]

Insulate the hull interior with fire resistant Armaflex. Other visible laminates painted with fire resistant acrylic paint..