Thanks, Peggie.

Brian


"Brian D" wrote in message
news:Qs%7c.68912$SR1.119804@attbi_s04...
Hey Peggie,

Your job stinks! (Always wanted to say that, heh heh.)

Got a question for you ...are all Porta Potty toilets created equal?
There are a lot of knock-off brands that cost a lot less ...is there
something we should know when comparing brands?

Thanks (and sorry for the off-hand remark),
Brian


"Peggie Hall" wrote in message
...
alex wrote:
Hi: I am building a 36' down easter,and would like your input on a
air
head toilet. please e-me direct, thank you Alex

Whether it's a good choice depends on where you're gonna put the boat.
Composters may be a good solution on a "no discharge" inland lake, but
in coastal waters where the discharge of treated waste is legal--which
is true of about 90% of coastal waters--it makes more sense IMO to
install a marine toilet and Type I MSD (i.e. Lectra/San for about the
same price and same power requirements.

Although composters reduce solids to very small amounts, there's the
matter of what to do with excess liquids. Some are evaporated, but not
all...They cannot legally be drained overboard inside 3 miles, so they
must be held aboard in something--the jugs provided with the Airhead or
a holding tank. The jugs have to be carried off the boat and dumped
ashore--so they offer no advantage over a portapotty...a holding tank to
store the liquids is still a holding tank that presents just as much of
an odor control problem as fecal matter...so what's the point of having
a system that separates urine from solid matter? Especially when you
consider that solids don't take up that much room in a holding tank
anyway.

Two people are gonna produce about a gallon of urine every 30 hours =
5.6 gallons of urine a week. Doesn't sound like much because it's
undiluted by flush water...but the odor-causing properties in it are
also undiluted.

And there's something else to consider: temperature. If you live in, for
instance Maine, where the summers are cool enough to need a jacket in
August, bacterial activity can be so sluggish that breakdown of
waste--composting--takes forever. In hot weather, bacteria are VERY
active...and the warmer the temperature, the more active bacteria (the
li'l buggers that create odor) are...making odor more of an issue.
Otoh, because a certain level of bacterial activity is necessary for
composting to happen at all, composters don't work very well when the
temperature is below 50 F. Since the Airhead doesn't actually compost,
but only removes all the moisture from solid waste, this may or may not
be an issue for winter liveaboards in cold climate zones, but it
definitely is for true composters unless the unit is heated
continuously.

And, there is the matter of power...it won't work without any, so it
must run when you aren't aboard to work...and power can be hard to come
by if you keep your boat on a mooring or don't have a shore power
connection.

So if someone who has a boat on an inland "no discharge" lake were to
ask me if I thought a composter is a good idea, I'd say it's definitely
an option worth considering--and the Airhead well designed, and well
engineered. But for boats in coastal waters--and especially those who
cruise offshore beyond the "3 mile limit" where the toilet can be
flushed directly overboard--there are no advantages--not even any
environmental superiority--to a composter over a traditional toilet and
a Type I MSD.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/html/get_ri...oat_odors.html