[Greenbuilding] Legionaires disease and water temperature

Michael O'Brien obrien at hevanet.com
Fri Dec 30 19:24:15 PST 2011

Hi, all--

Nick, please note that in the Quebec City study, none of the gas water heaters had Legionella while 33% of the electric heaters did.

See also: 

Lee, T.C., J.E. Stout, V.L. Yu. "Factors Predisposing to Legionella pneumophila Colonization in Residential Water Systems." Archives of Environmental Health 43 (1988);59-62 (available on PubMed.gov).

Lavoie, M., Levesque, B. and Sergerie, D. "Prevention of Scalding and Legionellosis Associated with Hot Tap Water in Private Homes"(www.inspq.qc.ca/pdf/.../197_PrevScaldingAndLegionellosis.pdf).


Mike O'Brien

On Dec 30, 2011, at 6:31 PM, Nick Pyner wrote:

> I think everybody boiled the whites once, not just the Germans. My mother did, I lit the fire under the copper, and Whakatane is a long way from Wiesbaden. Modern detergents make it usually unnecessary, and I could never advocate anything other than the usual cold water in the domestic arena, but it is still sometines done in hospital laundries. Those are serious machines that can dump water at 90C.  ( Heat exchanger heaven)
> Down here in GodsOwn we don't have a choice - 60 for stored water 50 for instant.  Solar-heated water is usually a lot more than 60 anyway. Electric storage heaters are banned from new construction.  Gas storage is virtually non-existant these days, and probably unavailable.
> I was far from impressed with O'Brien's comments. That on gas heaters being kosher at 49C because they heat the water from the bottom just seems absurd. While your bath water goes down the plughole the wrong way, I'm sure your convection currents are very similar to ours. Sediment collects in any storage tank and the same can be said for stratification of the temperature of the water, irrespective of the fuel that heats it. No comment on the hydronic pipes, but elemination of stagnant cool spots in the tank should be an interesting exercise.
> Nick Pyner
> Dee Why   NSW
> -----Original Message-----
> From: greenbuilding-bounces at lists.bioenergylists.org [mailto:greenbuilding-bounces at lists.bioenergylists.org]On Behalf Of Reuben Deumling
> Nice, Nick. 
> I thought that Michael O'Brien's summary of the issue was pretty succinct. 
> I didn't mean to imply that there was nothing to Legionnaire's disease, just that an unqualified across-the-board 60C requirement for water heater set points or 100C for washing white clothes is ill-considered, wasteful, ideological.
> It isn't as if climate change wasn't also expected to expand the range of well known diseases. Overheating our DHW is not an innocent requirement in the larger scheme of things.
> (Bill's cousin)
> _______________________________________________
> Greenbuilding mailing list
> to Send a Message to the list, use the email address
> Greenbuilding at bioenergylists.org
> to UNSUBSCRIBE or Change your List Settings use the web page
> http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/greenbuilding_lists.bioenergylists.org/attachments/20111230/e87f5c22/attachment.html>

More information about the Greenbuilding mailing list