NC Gas Chamber Regulations Mask Cruelty and Danger

Update March 20, 2012: Craven County has ended use of the gas chamber to kill shelter animals! 

Original report:This billboard stands as a reminder to Craven County, North Carolina residents that  pet animals, dogs and cats, are dying every day in gas chambers in their local shelter. 

A grass roots effort, the North Carolina Coalition for Humane Euthanasia (NCCHE), has been working to stop the use of carbon monoxide gas chambers as well as other cruel and inhumane methods of killing shelter animals in the state.

Davie’s Law, a bill introduced in 2009, would have done just that. The bill would have mandated use of lethal intravenous or intraperitoneal injection of sodium pentobarbital or similar substance. The bill was named for Davie, a dog that survived gassing by carbon monoxide in a North Carolina shelter.

Davie’s Law was assigned to the state House of Representatives Agriculture Committee which despite broad public support, never even voted on the bill, and it died in committee.  The North Carolina Dept. of Agriculture and Consumer Services ("Dept."), which regulates shelters, opposed the bill, insisting the Dept. would instead implement and enforce regulations for the continued use of carbon monoxide gas chambers.

This despite a national trend to prohibit the use of CO gas chambers in animal shelters. Relatively few animal shelters nationwide continue to use CO gas regardless. 

In North Carolina 25 counties still use CO gas chambers to kill shelter animals.  Find the list of shelters and their location here

This is the first in a series that will look at each North Carolina public shelter that still uses CO gas and the Dept.’s enforcement of its new regulations for CO gas chambers.

In 2009 NCCHE unearthed a number of inspection reports revealing gas chambers that leaked CO gas or otherwise simply didn’t work properly. There have been explosions and workers injured from CO gas. These reports were simply sitting in files with no apparent follow up by the Dept.  Find a summary of the violations here.

CO gas even breathed in at low levels when workers are loading or unloading or cleaning a gas chamber, for example, is a deadly health hazard. Attached below for downloading is a list of dangers to humans from exposure to CO gas.

Not to mention the abject cruelty to the animals as they cry, scream, claw and scratch to try to live.  Attached below for downloading are witness statements that establish the cruelty of using CO gas chambers. 

The American Veterinary Medical Association and the North Carolina VMA have given support for continued use of CO gas chambers, saying they are "acceptable" though not "preferred" as a means of killing shelter animals.  AVMA has many caveats and requirements for the use of CO gas chambers which, if summarized in one sentence, would basically state, if shelter workers can fit the proverbial camel through the eye of a needle, CO gas chambers are safe and acceptable.

One of their own, Ralph Houser, DVM, profits from manufacturing and selling CO gas chambers in the state. Houser not only makes and sells CO gas chambers, he is paid to provide the euthanasia "training" for many North Carolina shelters as well. In other words, the shelters provide a place for Houser to demonstrate his product and then pay him to show shelter workers how to use it! All under the guise of "training" shelter workers in "euthanasia".  Houser refuses to permit public access to the "training".

Also, in Lee County, for example, despite the likely conflict of interest, Houser has been paid by the county to consult and advise on animal control ordinances and specifically methods of euthanasia.  Houser serves on the Board of the state Animal Rabies Control Association.  On top of that, Houser does the inspections for the state for CO gas chambers he has sold to a county as well as others. A new regulation permits manufacturers to perform the annual inspections required of CO gas chambers.

It is therefore no surprise that CO gas chambers remain so entrenched in North Carolina. 

According to Peter MacQueen, former president of the Eastern North Carolina Humane Society, "some of the worst euthanasia problems in North Carolina take place at facilities where [Houser] has been the only euthanasia instructor".

Craven-Pamlico Animal Services

Under the new regulations only "commercially compressed, bottled gas" in a "commercially manufactured chamber" can be used by an animal shelter. 02 NCAC 52J .0601 A "commercially manufactured chamber" is defined as "a chamber built with the intention for sale with the purpose of euthanizing animals" and which meets the other requirements.[1] The idea is to have a chamber that is calibrated so that there is a minimum 6% uniform concentration of carbon monoxide gas within 2 minutes from the time the gas is turned on. A 10% concentration is explosive.

There is no way for shelter workers to measure concentrations of CO gas either inside the chamber or outside around seals and gaskets.  It is basically incumbent on the manufacturer to manufacture the chamber to ensure the concentration reaches 6% within 2 minutes. One manufacturer told NCCHE the formula used to make sure the chamber has a 6% concentration within 2 minutes is based on the assumption the chamber is empty and not filled with frightened animals. The longer it takes to fill the chamber and build up in the lungs, the longer animals suffer. (The concentrations are supposed to be tested during inspections with the use of a meter.)  

It would seem particularly important, then, that the Dept. at least enforce the requirement of a "commercially manufactured" gas chamber. But Lee Hunter, DVM, Director of the Animal Welfare Section of the Dept., has approved the use of a basically homemade device by Craven-Pamlico County Animal Services.  A class of welding students at Craven County Community College constructed the apparatus using steel plate and hinges. It was not built with "the intention for sale". In fact, the county did not pay the students or school anything for it.

In May, 2009 the county paid more than $8,300 to upgrade the student-made box with gauges, valves, dampers, exhaust outlets, a fan, ductwork and the like. 

Regardless, surely, no one could seriously suggest this school project meets the requirements of North Carolina law for euthanizing shelter animals. As Michele King of NCCHE put it, "But that still doesn’t make it a commercially made chamber, does it?  It’s like buying tires to put on a homemade wagon, then calling it a commercially manufactured car." 

Yet, Hunter claims "commercially manufactured" gas chamber means "constructed by someone else and they were paid for the resulting product". He seems to leave out all the other requirements. He insists there is nothing wrong with the county using the outfitted student-made gas chamber. (He has not yet responded to North Carolina attorney Jean Hollowell’s June 10, 2010 letter pointing out the Craven-Pamlico Animal Services is using the CO gas chamber in violation of the law because it is not "commercially manufactured".)  

In an October, 2009 inspection the local health department found levels of CO gas coming from the gas chamber: "Higher levels of CO could be found by surveying closely around door seals of both chambers and the thimble exhaust connection on the purge valve during fill cycle…"  No gas readings were disclosed, however.

Page 3: "CO escape around the purge valve of the larger chamber was improved markedly by reducing manual valve opening on the purge valve, while monitoring pressure differential…" Left to error of the operator.  But how much was leaking?

The CO levels were high enough that it was recommended employees stay out of the area when the gas chamber is in use. It is not clear how employees can comply with the regulation requiring a certified euthanasia technician and one other person remain present during the use of the gas chamber.  02 NCAC 52J .0609 Also, animals are supposed to be dead within 5 minutes while the gas chamber is to continue to run for 20 minutes. If no one is in the area, how does the shelter comply with the requirement the animals must be dead within 5 minutes?

The 2009 inspection report did not indicate whether the rigged gas chamber reached 6% of concentration of CO gas within 2 minutes. There is no indication levels of CO gas within the chamber were checked during the inspection. And the concentration of CO gas is surely less than 6% during use of the gas chambers if levels outside the gas chamber are dangerously high. That means animals are dying slower deaths, that their suffering is prolonged.

Also, animal services does not maintain warranties for explosion-proof components of the gas chamber as required by law.  There likely are none especially for a student project. Even the added components did not come with an explosion proof warranty.

Houser has been paid by Craven-Pamlico Animal Services to "train" staff in the use of the CO gas chamber. And he seems to be convincing county officials to continue to use CO gas chambers, however they are built.

In fact, the Craven County health director, Scott Harrelson, wrote one resident a spirited defense of use of the CO gas chamber.  Given the dangers of any exposure to CO gas, you would think a health director would be lobbying to get rid of it and bring Animal Services into the 21st century by encouraging humane euthanasia.

Instead, the 2009 inspection report reveals Harrelson had not even made sure warnings or instructions are posted for shelter staff. 

Harrelson made these comments, in quotes, in orange and italicized below, about what he as health director sees as advantages of using the CO gas chamber to kill shelter animals. Animal Law Coalition’s responses follow the quoted text:

"[Using a gas chamber means] can remove yourself from the area and perform other work duties".  But employees are asked to leave the area when the gas chamber is in use at this shelter because of the danger of leaking CO gas! Also, this is a direct violation of the regulations requiring the presence of a CET or veterinarian and one other person during use of the CO gas chamber. And, the shelter staff’s use of time should hardly be the concern of the health director.

"Once you factor in the staff time with injections the cost to do lethal injections begins to climb."  That is not correct. From the AHA study attached below, it is clear staff time is factored into cost comparisons and EBI is more cost effective. Unless maybe Houser is charging exorbitant rates for training the staff, inspections and "consulting". 

"It’s a lot easier to TEACH and supervise correct use of CO…"  It’s unlikely Harrelson would know this. It’s probably easier for Houser to teach and supervise use of CO gas chambers, but not for a trained Certified Euthanasia Technician or practicing veterinarian. Also, as King points out, "Should they use the method easiest for the teacher or most humane for the animals?"

Here is what the 2007 AVMA Euthanasia report states: The "preferred method" for euthanasia of animals is lethal injection by barbiturate sodium pentobarbital. "A primary advantage of barbiturates is speed of action. This effect depends on the dose, concentration, route, and rate of the injection. .. Barbiturates induce euthanasia smoothly, with minimal discomfort to the animal. … Barbiturates are less expensive than many other euthanasia agents….. The advantages of using barbiturates for euthanasia in small animals far outweigh the disadvantages. Intravenous injection of a barbituric acid derivative is the preferred method for euthanasia of dogs, cats, other small animals, and horses." For the animal, if administered properly, it is usually no different than having blood drawn or a shot given by a veterinarian, a fairly simple process. The animal can be held by an attendant while a veterinarian or technician administers the injection. An attendant can remain with the animal as it loses consciousness which happens very quickly. If the animal is or becomes aggressive, it can be sedated prior to the injection.

"Properly designed and maintained chamber". The law requires use of a "commercially manufactured" CO gas chamber and would not apply to the student project.  

"death in 10-12 seconds" This is impossible to prove and has been disputed by a number of studies. It can take longer just to fill the chamber with gas. Animals do not die until their lungs fill with CO gas. According to studies, "death as confirmed by cessation of heartbeat does not occur until 10-20 minutes after initial exposure to CO at concentrations reaching 6% (Moreland, 1974; Chalifoux and Dallaire, 1983; Dallaire and Chalifoux, 1985).[2] Lethal injection results in death in 30-60 seconds.  

"Any paddling or vocalization which does occur happens only after the animal is unconscious…" This doesn’t make sense. Surely, animals can bark or cry, scratch, struggle, howl, or scream when they are still conscious! A 2004 North Carolina Department of Labor Inspection Report for Sampson County Animal Control describes,  "The animal begins to struggle because it cannot breathe…They wait approximately 10 minutes until the animal stops making sounds…" The 2007 AVMA Euthanasia report states an inhalant such as CO gas requires high concentrations in the lungs before it is effective. Until there is sufficient build up of gas in the lungs, the animals experience a great deal of agitation. Here is how AVMA describes stress reactions of animals: "distress vocalization (this means barking, crying, howling), struggling, attempts to escape, defensive or redirected aggression, salivation, urination, defecation, evacuation of anal sacs, pupillary dilatation, tachycardia, sweating, and reflex skeletal muscle contractions causing shivering, tremors, or other muscular spasms."

Indeed, a few studies have reported that "prior to loss of consciousness dogs show signs of anxiety, including moaning vocalizations (Carding, 1968; Chalifoux and Dallaire, 1983; Dallaire and Chalifoux, 1985) and signs of agitation (Moreland, 1974; Chalifoux and Dallaire, 1983). Furthermore, there is some concern that the onset of convulsions (Close et al., 1996) and muscular spasms (Moreland, 1974) may precede loss of consciousness (Chalifoux and Dallaire, 1983; Close et al., 1997). Equally distressing behaviours have been observed in cats during the initial phase [of death by CO gas].  (Simonsen et al., 1981)."

AVMA acknowledges "[u]nconscious as well as conscious animals are capable of some of these responses. Fear can cause immobility or "playing dead" in certain species, particularly rabbits and chickens. This immobility response should not be interpreted as loss of consciousness when the animal is, in fact, conscious. Distress vocalizations, fearful behavior, and release of certain odors or pheromones by a frightened animal may cause anxiety and apprehension in other animals."

There is no question shelter workers have documented the piercing cries, howling, frantic calls, scratching and panic of animals as they are gassed. Just putting them in the chamber is frightening for animals. The chamber is hot, confining and often smells probably like death. They don’t know what is happening and they immediately experience panic and distress.  See the attached statements from witnesses to gassings of shelter animals

"…take 2-5 breaths and reach level III of unconsciousness"  There is no proof at all of this and in fact studies confirm unconsciousness may take up to 2 minutes and animals have been found to have survived gassing. (Moreland, 1974; Chalifoux and Dallaire, 1983; Dallaire and Chalifoux, 1985)[3]. Davie is one example. Also, how could the staff possibly count the breaths or otherwise verify if and when the animals reach unconsciousness? Particularly given the directive for them to stay away from the area while the gas chamber is in use?  The reality is that animals are slowly asphyxiated by poisonous CO gas until they finally succumb, many times crying, screaming, gagging, gasping for breath, beating their heads against the chamber walls and clawing to escape.  A former volunteer for the Craven-Pamlico shelter described "popcorn kittens" jumping around frantically in the gas chamber. 

The AVMA report states, "Reptiles, amphibians, and diving birds and mammals have a great capacity for holding their breath." The report goes on to state in these animals which include dogs and cats, the time to lose consciousness "may be greatly prolonged."

"…Animals with depressed circulatory issues bleeding out from HBC actually do better with CO…."  Just the opposite. CO gas does not render an animal unconscious until there is a build up of CO gas in the lungs. This is very difficult for young, old, pregnant, sick or injured animals.  The buildup of gas in an animal’s lungs is slower if there is decreased ventilation or diminished breathing capability as that associated with young, old, pregnant, sick or injured animals.  

A study has shown baby animals take longer to die in gas chambers. AVMA reported, "Dogs, at 1 week old, survived for 14 minutes compared with a 3-minute survival time after a few weeks of age. Guinea pigs survived for 4.5 minutes at 1 day old, compared with 3 minutes at 8 days or older. Rabbits survived for 13 minutes at 6 days old, 4 minutes at 14 days, and 1.5 minutes at 19 days and older." Gas is not recommended by AVMA or any other group for animals under 16 weeks of age. The same effects have been reported for old or sick animals as well. Unfortunately, these are the animals most likely to end up in a gas chamber. It is not uncommon for these animals to be gassed a second time before they finally succumb.

Even the North Carolina regulations prohibit use of the CO gas chambers for animals under 16 weeks of age, pregnant or near death. 02 NCAC 52J .0602

Harrelson also claimed an employee at the shelter did not want to hold animals as they were injected with sodium pentobarbital. She or he apparently prefers shoveling them into a CO gas chamber. Actually, with proper training and a professional attitude, most shelter staff would agree EBI is far more humane and the better method of putting down animals. And that’s really the point and it is why the vast majority of shelters in the U.S. and North Carolina use EBI. 

Craven-Pamlico Animal Services Supervisor Kathryn Smith claims, "It costs $3.25 to put a dog down with carbon monoxide as opposed to about $7 when we do it by injection". According to a 2009 study by the American Humane Association, however, it costs about $4.66 per animal to use CO gas chambers to kill shelter animals in North Carolina, while the cost of euthanasia by lethal injection is approximately $2.29 per animal including the cost of staff.

The counties’ commissioners should ask where the extra money is going. Who is profiting from the continued use of CO gas in Craven-Pamlico?  As the 2009 AHA study indicates, it should only cost about $2.29 per animal to use lethal injection. Smith incidentally is on the Board of Directors for North Carolina Responsible Animal Owners Alliance, an organization of breeders and other national interest groups generally opposed to animal welfare laws. NCRAOA actually paid a lobbyist to oppose Davie’s Law. 

The NCRAOA attitude is reflected at the Craven-Pamlico Animal Services shelter. Smith and Harrelson have announced that the animals in shelters are not really pets, that they are feral or wild. I doubt either could properly determine whether a cat is truly feral or simply very afraid.  Either way it is surely much safer to sedate and euthanize by lethal injection than manhandle or drag a scared animal, feral or not, to a gas chamber. Most of the animal shelters in North Carolina and around the country have found that to be the case.

And whatever name Smith and Harrelson give to these animals, there are pets dying every day in these shelters – in a cruel and inhumane way. You know it and Craven-Pamlico County officials know it.

Join us on Facebook  to learn what you can do to stop use of CO gas by Craven-Pamlico County Animal Services to kill shelter animals.

Brunswick County

When the new North Carolina euthanasia regulations went into effect in 2009, Brunswick County was using a CO gas chamber constructed by a local welding shop.  Concerns were raised, though not by the Dept., that the device was not "commercially manufactured" as required.  But instead of opting for euthanasia by lethal injection of sodium pentobarbital, the humane option "preferred" by AVMA, the county decided to buy a CO gas chamber at a cost of $12,000 to the county taxpayers from Cutting Edge in Gastonia.

The CO gas chamber had been rebuilt, however, and had a leaky, defective valve.  At last check, the county still did not have a flow meter to indicate the levels of CO gas inside the chamber during use or outside around the valves and seals.  There still appears to be no compliance with the new regulations requiring warranties that are explosion proof.

A December 21, 2009 report of a site visit states the level of CO gas was said to be 9% inside the chamber when it is in use though it is not clear how this was determined. A 10% concentration would result in an explosion. For levels outside the chamber, the inspector simply noted "no levels of carbon monoxide above background".  No specific levels were stated.  

The report recommended "inspection and any necessary repairs/replacements at least monthly for chamber seals, exhaust flow, carbon monoxide monitors and other equipment". The report also noted the requirement for an annual inspection by the manufacturer or representative or an industrial hygienist. The inspector recommended use of a CO monitor in the vicinity of the chamber.  

Houser conducts the euthanasia training for Brunswick County. Employees can only hope the CO gas chamber county officials insist on using doesn’t explode or cause them serious illness or death, either now or later in life.

Join us on Facebook to learn what you can do to help stop use of CO gas to kill shelter animals in Brunswick County.

Look for information about the effect of the new state regulations on the use of CO gas chambers in other North Carolina counties in upcoming reports in this series by Animal Law Coalition. 



(a) A euthanasia chamber in a certified facility shall be located in a well-ventilated place, preferably outdoors.

(b) The chamber shall be in good working order.

(c) The chamber shall have strong airtight seals around the doors and viewports.

(d) The chamber shall have at least one port for viewing of the animals during euthanasia.

(e) The chamber shall be lit sufficiently to allow observation of an animal in any part of the chamber.

(f) Any chamber electrical wiring or components exposed to carbon monoxide must be warranted by the manufacturer to be explosion proof.

(g) Any light inside of the chamber shall be shatterproof.

(h) The chamber shall use exhaust ventilation to evacuate the gas from the chamber before the doors are opened upon completion of the process.

(i) If the chamber is located outdoors:

(1) The exhaust shall be vented at least eight feet above ground level.

(2) The minimum stack velocity shall be at least 3,000 feet per minute;

(3) If there is a roof above the chamber, the exhaust shall be vented at least three feet above the highest point of the roof; and

(4) The exhaust shall not be located within eight feet of any building air intakes.

(j) If the chamber is located indoors:

(1) The exhaust shall be vented to the outdoors at least three feet above the highest point of the roof;

(2) The exhaust shall not be located within eight feet of any building air intakes;

(3) The minimum stack velocity shall be at least 3,000 feet per minute; and

(4) At least two carbon monoxide detectors shall be placed in the room.

02 NCAC 52J .0601 requires: (1) Only commercially compressed, bottled gas shall be used;

(2) The gas shall be delivered in a commercially manufactured chamber that allows for the individual separation of animals;

(3) Animals placed inside of the chamber shall be of the same species;

(4) The chamber shall achieve a minimum six percent uniform concentration of carbon monoxide within 2 minutes of beginning the administration of the gas.

[2] http://www.wspa/


[3] http://www.wspa/