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This solution may be mixed from nonionic detergent and
any one of several chlorine containing compounds such
as calcium hypochlorite, or laundry bleach.
In storage, compounds containing chlorine have
been known to deteriorate.
It will be necessary,
therefore, to have a qualified person from the ships
company analyze the soaking solution for chlorine
content to make sure the proper concentration of
available chlorine is attained and continued at sufficient
strength.
After the sterilization, soak and water rinse, cover
the washracks containing the utensils with a cloth that
has been sterilized by boiling. Do not transfer utensils
to another rack. Make sure personnel in the serving line
pick up utensils from the washracks by touching only
the handles.
Large equipment may be decontaminated by the use
of hypochlorite. Hypochlorite is corrosive to all metals
that will rust and should not be allowed to come in
contact with motors and other electrical equipment from
which hypochlorite could not be thoroughly wiped off.
After decontamination, cover as much of the equipment
as possible with clean cloths to prevent recontamination.
Avoidance of Recontamination
Recontamination may be caused by secondary
aerosols that resettle organisms on surfaces or
contaminate the air that is breathed. Secondary aerosols
are clouds formed from particles (bacteria or other
organisms) that, having been deposited on a surface, are
stirred up into the air again by scuffing, shaking, or other
mechanical action.
Secondary aerosols may be
suppressed by wetting surfaces with oil or water. If oil
is used as a suppressant, it must not generate harmful
vapors and it must not be applied to walking surfaces
which may create slippery conditions.
It is important to make sure, before entering the
messing area, MS personnel and all personnel eating in
the messing areas are as free as possible from
contamination. The medical officer should be consulted
on the decontamination of foodservice personnel. In
cold weather, personnel in the serving line should be
required to remove outer garments and leave them
outside the messing area before entering the mess. It
has been found that removing clothing will shake off
organisms that have come in contact with the surfaces,
thereby setting up secondary aerosols. Do not permit
unauthorized personnel in foodservice spaces.
Hypochlorite is a strong oxidizer and, in powdered
form, reacts violently with oils and greases. Use
hypochlorite in a well-ventilated area. Always wear
goggles and protective gloves, and consult the MSDS
for additional precautions.
Decontaminating Food Items
The advice of the medical officer must be sought
before any attempt is made to decontaminate food
suspected of biological contamination.
Semiperishable Food Items
Food packed in containers that are resistant to the
passage of biological agents (sealed containers made of
metal, plastic, glass, or porcelain) requires only proper
exterior decontamination be performed. Paper labels
and paper covers must be removed from the container
and one of the following methods of decontamination
should be used:
1. Immerse the containers for 15 minutes in a
solution of water to which 200-ppm available chlorine
has been added and then rinse them with potable water.
2. Soak the containers for a minimum of 15
minutes in effective detergent solution as a quick
method to reduce contamination to a safe level (see
formula 1 discussed under the heading Radiological
Decontamination); then rinse them with potable water.
3. The exterior surfaces of stacks of food packed
in impermeable packages can be sterilized using any of
the standard chemical methods such as bleach solution,
sodium carbonate, or DS2 followed by rinsing in potable
water.
Food packages that will not stand immersion must
be wiped off with a solution of water to which 200-ppm
available chlorine has been added and the food
thoroughly cooked before it is eaten.
Fresh or Chill Items
Food that can be peeled or pared may be
decontaminated by soaking for 15 minutes in water to
which 200-ppm available chlorine has been added
before it is peeled. The food must then be thoroughly
rinsed in potable water. It can then be peeled or pared
and should be rinsed again with potable water. This
method has been applied satisfactorily to apples,
potatoes, and eggs.
For other fresh or chill items, the use of heat is the
most practical means of decontaminating foods.
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