Below are a few links to videos demonstrating the effectiveness of fire retardants used on timber substrates. Hopefully it will give you a brief insight into how they can be used in a much larger scenario.

Note the second one is an intumescent coating which will be similar to ones we test, i.e. they use solid phase char formation to insulate the wood.

1 - Timber Fire Retardant

2 - Intumescent Coating Used on Wood