Hi, I've found this website www.burglarybusters.ie and they claim to have doors that are more secure and still compliant with fire safety regulations. 

Do you know if these are really admissible or it's just them adjusting their marketing to what's required?

Thank you

You could ask them to provide evidence of performance for fire resistance and restricted spread of cold smoke. 

ok I will. For the cold smoke do you think these type of doors that form like a seal with the frame need the same type of intumescent with brushes? In that case wouldn't be a noise/weather seal be the same? Of course the intumescent needs to be there, I'm not sure about the brushes

 

There are various types of smoke & acoustic seals. Eg: https://www.lorientuk.com/products/acoustic-smoke-and-fire-door-seals/acoustic-smoke-and-fire-seals  Safelincs most likely supply a similar range of seals. 

Thank you!