Common sense tells me both.
If you go through one pane you will go through both.
Agreed Bob, a tempered sash is a tempered sash.
tempered one side only, what if the factory makes a mistake and installs it backwards. ???
That’s my take on it.
Marcel :)
Agreed and thanks.
I believe all glass is required to be tempered if it is within 18" of a door, 12" of the floor, and 60" above a shower/tub drain.