I'm aware that some windows/glazing ought to be provided to a certain standard (BS2606?) but am not sure why some are stamped, and others not.... Is there a simple system? Is it simply that a certain size, and above, needs to be stamped? Or something else? I ask as we've recently taken possession of a new building and the handover is not as smooth as planned and so want to ensure consistency across the whole, and to the correct standard. Cheers for any advice Pete

Fire rated glazing : Laminated must have BSEN 14449 name of manufacturer and 30E or E30 Wired BSEN 572 name of manufacturer and 30E or E30 Reason - how else would you know if it was FR glass?

Chris has given you the stamp info but I think you didn't ask specifically about Fire Resisting? It should be noted that the laminated fire resisting glass (Pyrodur and Pyrostop) is a safety glass. The clear wired glass can also be a safety glass although the obscured wired may not be a safety glass anymore. Toughened glass will be stamped with BS6206 or EN12150 and there is no minimum size - if it is a safety glass then it should have a stamp and it should be visible after the glass has been glazed.