Fire Retardant Doors on Olympic's 1933 GA plans?

[Cam Houseman]

Hi y'all

When were these "FRDs" added? I heard they were Fire retardant doors. They're most visible on Olympic's 1933 General Arrangement plans on the hallway aft on B and C-Decks

thanks for the help!

 

[Mark Chirnside]

They're certainly shown on 1919 plans.

 

[Cam Houseman]

They're certainly shown on 1919 plans.

Ohh, thanks Mark.

Were these added because of new Fire regulations?