HH62/2/LANARK/94

Transcription

[Page] 93

disinfected are placed, the doors closed, and steam intro-
duced into both jacket and central chamber. Two gauges
mark the pressure within jacket and chamber respectively,
and at the same time indicate the temperature - the pres-
sure and temperature in the jacket being kept higher than
in the chamber in order to super-heat and dry the contained
steam. The steam from the chamber, after a period of
twenty minutes or half-an-hour, is then allowed to escape,
and the articles should remain until dried by the heat
caused by the steam in the jacket. Disinfectors of
this pattern are at work in nearly all the large towns in
England and Scotland, and my own experience of them
has been satisfactory. There are, however, one or two
drawbacks. The doors not being jacketted are colder than
the rest of the machine, and consequently condensation
occurs, which for various reasons is a disadvantage. Again,
there was no arrangement for displacing the air in the
chamber before beginning to disinfect; and this air inter-
feres to some extent with the penetrative power of the
steam. A third objection was that the drying of the
clothes was not quite satisfactory. In actual practice I
found that by careful manipulation these difficulties might
be almost entirely overcome. Still, they suggested that
improvements were required.
Accordingly, Messrs. Goddard, Massey, & Warner, of
Nottingham, the makers of one of the best of the old hot
air ovens, brought out a disinfecting apparatus which has
had considerable success. It is of rectangular shape,
with rounded corners, and gives considerably more room in
the chamber for mattresses, &c., while the makers assert
that by proper stays in the jacket the flat sides are strong
enough to stand all necessary pressure. The doors are
jacketted, and supplied with steam by means of a double-
jointed copper pipe, which allows the doors to open. By
this contrivance condensation on the doors is avoided. By
means of a coil, hot air can be introduced into the chamber,
and thus displace the cold air prior to the introduction of
the steam, and after disinfection, hot air can again be
introduced to dry the clothing and other articles.
In addition to these advantages the apparatus has been
so arranged that it can be heated by a fire forming part of
the machine - using the jacket as a boiler and thus saving
the necessity of a separate boiler.
Quite recently, Manlove, Alliott, & Co., have introduced

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further improvements into the Washington Lyon Dis-
infector, and they are now supplying it with coil, jacketted
doors, and so arranged that the same machine can be worked
either by steam generated in the jacket, or by steam intro-
duced from a detached boiler. Both of these machines
were adopted by the Bradford Corporation by my advice
(that made by Manlove, Alliott, & Co., being the first of
the kind), and are now working admirably.
The relative disinfecting power of Steam and Dry Heat
is as follows:-
(a) Dry Heat, at 220° F., ---4 hours.
Dry Heat, at 245° F., --- 1 hour.
(b) Steam, at 212° F., --- 5 minutes.
Steam is therefore the most expeditious and reliable, and
is free from the danger of scorching, but, as already stated,
leather is immediately spoilt by it.
One of the disadvantages of steam is that stains in
fabrics are fixed by it so that they cannot be removed by
washing. This is an additional reason for the erection of
a wash-house in connection with a disinfecting station, as
stained articles, and all washable articles, can be dealt with,
and then, if necessary, submitted to the heat of the dis-
infectors.

Chemicals. - (a) In Solution. - To these I have already
referred. They are only of use where heat is inapplicable
as in dealing with excretions or discharges from patients
suffering from infectious diseases, and notably in the case
of typhoid patients where the poison is contained in the
discharges from the bowels.
They are used also for scrubbing floors, woodwork, &c.
The best of all is mercuric chloride in a solution of
1 in 1000. Sanitas, creolin, and carbolic acid are also useful.
(b) As Vapour. - Disinfectants in the form of vapour or
gas are used in infected rooms in order to, if possible,
destroy those germs which cannot otherwise be reached.
Perhaps the best, as already indicated, is chlorine in the
presence of moisture, although sulphurous acid is supposed
to act powerfully upon organic matters.

In considering the whole question of disinfection it is
absolutely necessary to bear in mind that the mere removal
of offensive smells does not therefore mean the destruction
of infective power.