Airzone

AIRZONE OZONE AIR PURIFIERS FOR MORTUARIES AND COLD ROOMS

Ozone Pollution Technology 1998

Introduction
Ozone is enriched oxygen and is nature’s powerful purifier. It is a short lived molecule that
deodorises many organic and inorganic odours, both gaseous and particulate. It does this by
a process of oxidation, permanently converting the odour into water vapour, carbon dioxide
and other compounds. It kills germs by breaking down their protein structure.
Ozone is approximately 1.5 times more reactive as an oxidizer than chlorine. It also reacts up
to 3000 times faster with organic materials such as bacteria. Unlike chlorine, ozone is highly
effective against viruses as well. Importantly, ozone leaves no chemical residue as unused
ozone decomposes back into oxygen. Since ozone is generated on-site, the safety problems
associated with chemical storage, handling and transportation are eliminated.
Utilisation of ozone for increasing the storage life of food, particularly if held at low
temperatures, is believed to have started in 1909 when, in the cold-storage plant of Cologne,
the reduction in the germ count on the surface of meat stored there was observed after an
ozone generator had been installed in the duct of fresh air used to ventilate the storage room.
The many possibilities for using ozone in the food industry and agriculture as well as in other
fields are created by its bactericidal and germ-killing power. Not only does it act as a
germicide but as a spore-killing agent as well. Foods and carcasses exposed to its effect, undergo a
pronounced change as a consequence of its action on the vital process of cells, the process
of their metabolism particularly, through the inactivation of their metabolic products. At the
same time it reacts with other materials present that can be oxidized and thereby it destroys
odours.
Utilisation of these properties makes ozone eminently suitable for unrefrigerated or refrigerated premises. Its use is economic as the investment and operational costs of the equipment are acceptable in relation to the size of rooms or freezers. Its application eliminates the risk of leaving the unpleasant odour or other traces of antiseptics used for preservation.
Micro-organisms
The microbial structure of a cadaver depends on the surrounding atmosphere at the time of death such as drowning for example where the condition of the water will determine the microorganisms present. The mucus protection on the skin of the cadaver can contain the following types of bacteria: pseudomonas, achromobacter, micrococcus, flavobacterium, corynebacterium, sarcina, serratia, vibrio andbacillus. Bacteria found on bodies from cold waters are usually psychrophilic, whilst whose
found on warm water fish are mesophilic. Fresh water bodies carry bacteria peculiar to those
waters, in addition to many of those found in salt water, and species of aeromonas,
lactobacillus, brevibacterium, alcaligenes and steptococcus. In addition to those bacteria
mentioned above, species of clostridium and escherishceria have been found in the intestines
of all kinds of bodies.
The number of bacteria in the mucus and on the skin of a body can vary from 100 per sq. cm to several million. Its intestinal fluid can contain anywhere from 1,000 to 100 million bacteria per ml. The skin can play host to between 1,000 and 1,000,000 per gram. Although rinsing reduces the surface bacterial count, it is obvious that this is not adequate.
Storage
A human body is susceptible to autolysis, oxidation and hydrolysis of fats and microbial changes. Therefore, rapid preservation treatment after death is recommended.
Rigor mortis is an important factor in the preservation off bodies, since it delays post-mortem
autolysis and subsequent bacterial decomposition. Any process which prolongs rigor mortis
will therefore extend the preservation period. A major factor in this process is a reduction in
storage temperature. Nevertheless this process is not sufficient in itself as most of the
bacterial colonies mentioned can survive at low temperatures, and even at those approaching
freezing point.
Reducing contamination is difficult to achieve using aseptic procedures.
Use of Ozone During Storage
The elimination of bacteria is a difficult process, but the fact that most germs causing
contamination are found on the outside surface of the cadaver means that treatment with ozone is
very effective, even in small doses.
Bacteria congregate on the surface of the skin. Ozonization actually prevents bacterial decomposition by destroying the bacteria, thus postponing post-mortem autolysis. As a result, rigor mortis is sustained for a longer period of time. This affects the preservation of the body favourably. Rinsing the body with water containing low concentrations of ozone helps to reduce the total bacterial presence on the surface of the body considerably.
The Fishing Industry( A useful comparison)
A useful comparison is the fishing Industry where experiments with Ozone Purifiers have been conducted to cover each stage through which the fish passes on its way to the consumer.
Ozone is used in Japan and Europe in the fishing industries to disinfect the water used for on
board processing and ice making. Benefits include reduced mould and bacteria counts on the
gutted fish. Treated fish are found to have counts of less than 1/1000th those of fish
processed with untreated water and untreated ice (Bull, Japanese Soc. Fisheries 1979).
Sensory and analytical studies indicate the use of ozone does not cause development of
rancidity and the eating quality of fish processed in ozone treated water is better than the
control.
A trial was conducted on shellfish in the hold of a fishing vessel, with the hatch opened 3
times a day only. An Ozone Purifier was placed in the hold and ozone was introduced at a
concentration of 1.1 mg/hour per cubic metre of hold volume for an 18 day period. As a
result, permitted preservatives were reduced to 10%. Odours in the hold were totally
eliminated. The appearance of the shellfish after 15 days was striking. Discolouration of
shellfish heads was actually eliminated (prawns, crayfish, etc.) The colour suggested that the
shellfish had been caught the day before the vessel was put into port. The shellfish was at the
rigor mortis stage. The rate at which the ice placed in the hold to freeze the shellfish melted,
dropped by 70%. The floors of the hold were completely dry after the shellfish were unloaded.
The experiment was repeated on board another vessel from the same fleet used for mackerel
fishing, for a 3 day period, at the same rate of 1.1 mg/hour per cubic metre of hold volume. As
a result, no preservatives were required. No odour was detected. The fish were at the rigor
mortis stage. No rancidity was evident, either in the form of smell or taste.
A trial was conducted in a processing area using a concentration of 1.5 mg/hour per cubic
metre of space. Several Ozone Purifier units were installed. The trial consisted of leaving the
industrial waste from the day’s processing in the area. The batch processed that day
consisted of several tons of assorted fish. All windows and doors were kept closed until 7
a.m. the next day. Upon inspection at 7 a.m., deodorization of the area was 100%. For the
first time ever, the computer installed in the processing area worked perfectly, which was
unusual because of the high humidity concentrated in the area.
Specific studies on freshly caught Alaskan salmon found that the storage life could be
extended by 33% to 50%, and that the development of rancidity was significantly slower when
the salmon were washed and iced with ozonated water/ice.
Fresh fish in a self-service retail cabinet have been shown to extend their shelf life by 1 to 3
extra days when Ozone Purifiers were used. Odours were eliminated at the same time.
Refrigeration
Autolysis starts once the person dies. This is accompanied by loss of firmness and the
development of abnormal odours; bacterial growth is uncontrollable under these conditions.
As already mentioned, these changes are postponed by rigor mortis. Preservation by means of refrigeration or cooling is temporary at best, due to the fact that muscular tissue autolises and its fats oxidize at temperatures slightly above freezing (rapidly during summer and more slowly as freezing point is approached). Smaller bodies generally deteriorate more rapidly than larger ones.
Use of Ozone During Refrigeration
The addition of relatively low concentrations of ozone to cold rooms helps to destroy most of
the bacteria on the surface of the bodies, preventing spore propagation inside the room. This
can be achieved with intermittent doses from an Ozone Purifier with concentrations of about
0.9 mg/hour per cubic metre of volume.
At these concentrations, ozone does not contribute in any way to an acceleration of rancidity
as a result of an acceleration In the oxidisation of the body, since the body and other microrganisms deteriorate through autolysis, which is a bacterial process. Ozone dosages act by paralysing the bacterial activity, and as a result, delays autolysis without ever reaching the oxidizational stage, since bacterial changes in body do not commence until after rigor mortis, which is when the muscular tissue begins to release its fluids. Therefore the more this stage is delayed, the longer the body can be preserved. Rigor mortis can be accelerated by stress at the time of death or by lack of oxygen and high temperatures.

THE AIRZONE SYSTEM

The units are positioned in a clean dry air outside of the freezer and an air pump inside the enclosure pumps the ozone gas in to the freezer through a 6 mm pipe and a timer allows regulation of output and treatment schedules.

Airzone Mortuary Model A = Body cabinets 6 bodies on 2 layers
Airzone Mortuary Model B = Freezer rooms up to 25 m2
Airzone Mortuary Model C = Freezer rooms 25 to 50 m2
Airzone Cleopatra = Large Offices
Airzone OdoFree Sani = Small Offices, toilets, storerooms and passages