From ANIMAL PEOPLE, October 2006:
After claims that gassing is safer for employees, the most
persistent argument for killing animals by carbon monoxide instead of
sodium pentobarbital is that carbon monoxide is less expensive–if
only because most of the gas chambers now in use were installed and
paid for decades ago.
“Switching to lethal injection would mean investing in drugs
and training staff,” reported Raleigh News & Observer staff writer
Marti Maguire in February 2006. “That could strap counties that now
spend as little as $20 per animal. The Orange County shelter spends
$150 per animal,” using lethal injection, Maguire wrote.

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From ANIMAL PEOPLE, October 2006:
Are the surging numbers of dangerous dogs
entering animal shelters retarding progress
toward abolishing gas chambers?
Warren Cox began to wonder in May 2004
when he arrived for a stint as interim executive
director at the Montgomery County Animal Shelter
in Dayton, Ohio, and found a carbon monoxide
chamber that only a few days before was still in
sporadic use.
Having managed more than two dozen
shelters since 1952, Cox knew he was looking at
an anachronism. The Dayton chamber had
supposedly been decommissioned years earlier.
The Dayton Daily News published exposés of
gassing in nearby Fayette County and Darke County
in 1995 and 1997 without apparent awareness that
animals were still gassed right there in Dayton.
Continued gassing at the Mont-gomery
County Animal Shelter came to light as result of
a September 2003 complaint to county officials by
veterinarian Sue Rancurello and shelter
volunteer Jodi Gretchen, and was discontinued
after a shelter evaluation by American Humane
affirmed the obsolescence of gassing.
“Two top administrators at the Montgomery
County Animal Shelter were removed,” the Dayton
Daily News reported, in part for “using carbon
monoxide instead of lethal injection to euthanize
more than the recommended number of animals.”
Cox had the carbon monoxide chamber
removed. But Cox also took note of who used it,
and why. Throughout the first half of Cox’s long
career in shelter work, carbon monoxide, carbon
dioxide, nitrogen, and decompression chambers
were used to kill animals in high volume. The
Dayton gas chamber was used to kill specific
animals whom some of the staff considered too
dangerous to handle.

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