MOC301x is ok for use in the US - in countries with 220 or 240VAC you
will need MOC302x optos.
Hadn't thought of that. The app note has a schematic for using two in
series to switch 240v.
you could if you had to - but why use 2 triac drivers and voltage
sharing resistors and capacitors and twice the drive requirement when a
component rated for 240V RMS blocking is readily available?