On 12/9/2016 4:21 PM, Ralph Mowery wrote:
In article , lid
says...

Per Ralph Mowery:
As the smoke alarm is uusually mounted high and the
CO is mostly low, they peobalby will not go off soon enough.

That's good to know.... Thanks.

I have to take that back. Carbon Dioxide is heaver, the Monoxide is
slightly lighter.

Would not make any difference. They are miscible. Otherwise oxygen and
nitrogen would separate.