"Brian Reay" wrote in message
news
On 17/09/2018 23:12, Peter Parry wrote:
On Mon, 17 Sep 2018 21:12:48 +0100, "Jim GM4DHJ ..."
wrote:

are optical smoke alarms better for less false alarms than ionising
ones...in practice I mean ? .....

No. Neither have significant false alarm rates. Both however can
suffer nuisance alarms, these are not false alarms but real alarms
produced by non- dangerous activities such as steam from a bathroom
or overheated toast.

Optical suffer more from steam, ionisation from the combustion
products of things like singed toast. Used and sited properly neither
should have a significant nuisance alarm rate (unless of course you
are prone to overheating toast with the toaster is in the bathroom
sink while you are taking a shower).


There are different types, at least 3, of detectors which are recommended
for different rooms/areas for just the reasons you say. Placing the right
one in the right location/checking it has been done is the kind of thing
I'd expect a competent Building Inspector to be able to do. May be a call
to the local council?

optical detectors were uncommon in the battery powered domestic situation
when I retired in 2010 .....I mainly dealt with things like shopping centres
and an airport.....I left chicken feed to my staff....tee hee