2002 NEC 210.4(B) does
not require a common trip breaker, this was pointed out to me on this forum in another post.
You can use a common trip breaker or you can use a approved handle ties with single pole breakers.
2002 NEC
210.4 Multiwire Branch Circuits.
(B) Dwelling Units.
In dwelling units, a multiwire branch circuit supplying more than one device or equipment on the same yoke shall be provided with a means to disconnect simultaneously all ungrounded conductors at the panelboard where the branch circuit originated.
2002 NEC Handbook commentary on this.
The simultaneous disconnection can be achieved by a 2-pole circuit breaker or by two single-pole circuit breakers with an approved handle tie,
[This message has been edited by iwire (edited 06-13-2003).]