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Chapter XXXVI

Books and Documents > Medical Department of the U.S. Army in the World War, Volume III, Finance & Supply




The selection of a suitable type of sterilizer for surgical dressings that would be needed in our many military hospitals presented a matter of considerable importance to the supply division of the Surgeon General’s Office upon our entrance into the World War. A few electrically heated sterilizing outfits had been purchased for Army hospitals during the years 1910-1916. Due to lack of attention on the part of the operatives, these outfits were a source of annoyance to the supply division. In consequence of this experience and of reports from civilian hospitals, it was decided to limit the sterilizing apparatus for the large fixed hospitals during the World War to those using high-pressure steam. With each set of sterilizing apparatus, as a part of it, there was furnished a steam boiler of suitable size and of the vertical submerged-tube type. The apparatus furnished at first were equipped with a 6-horsepower boiler of this type. It soon became evident that a large-sized boiler was required, and subsequent outfits were provided with 10 or 12 horsepower boilers. It was desirable to install large sterilizing chambers, or disinfectors, for the disinfection of mattresses and bed linen. While the 6-horsepower boiler could provide steam for either the sterilizing set or the disinfector when operating alone, it was inadequate when both were operating simultaneously. The large-sized boiler, while using but little more fuel, satisfactorily met these requirements.

In compiling the list of apparatus for sterilizing outfits for the camp hospitals, it was decided to limit it to the following pieces and sizes, all sterilizers to be suitably mounted on separate stands or in groups on one or two stands:1 One 16 by 36 inch dressing sterilizer, or one of approximately equal capacity; 1 pair of 25-gallon water sterilizers complete with filter; one 20 by 20 by 24 inch utensil sterilizer; one 7 by 12 by 22 inch instrument sterilizer; One 6-horsepower steam boiler; one set of piping.

The sizes selected were standard commercial sizes, and no difficulty in their manufacture was anticipated. Such delays as might arise would be those incident to securing raw materials and semifinished parts and the time required for the manufacture of the apparatus. No maker of sterilizer apparatus was equipped to draw the shells of the water sterilizers. These shells are of brass and to draw them requires special skill and apparatus. They were obtained from one or two firms equipped to draw them.

In April, 1917, five or six firms in the United States were making sterilizer outfits. Each of these firms had a design of its own. While all were of the same general type, they differed in minor details of manufacture. On April 15, 1917, these manufacturers met in Washington and appointed a committee


on sterilizing apparatus to develop standard specifications and plans for production.1 Specifications, prepared by a subcommittee appointed for the purpose, were considered and adopted on the following day. These specifications were sufficiently general to cover the apparatus commonly made by the several manufacturers. They were as follows: 1


(United States Army medical supply depot)

*  *  *  * * *

Each sterilizing outfit to consist of the following:
One 16 by 36 dressing sterilizer.
One pair 25-gallon, capacity each, water sterilizers complete with filter.
One 20 by 20 by 24 utensil sterilizer.
One 7 by 12 by 22 instrument sterilizer.
One 6-horsepower steam boiler
One set of piping.

The following detailed specifications are to be observed:

The dressing sterilizer to be of the steam-jacketed type, with a separate generator in which the steam for sterilizing will be generated.

The inner, or sterilizing chamber to be formed from a seamless, cold-drawn, brass shell, tinned inside, and the outer or pressure chamber to be of brazed or riveted copper construction. The door and door frame to be made from high-grade cast bronze, and the door to be locked by radial locking bar, controlled by a handwheel.

The steam generator to be constructed from brass or copper, to have sufficient water capacity to carry through two sterilizations of material without refilling. One end of the generator to be easily removable for cleansing of sediment from the interior.

The construction of the sterilizer to be such as to permit sterilization of its contents by subjection to steam at 15 pounds pressure for 30 minutes, after which dry sterile dressings are to be available within 3 minutes.

The steam jacket and generator to be subjected to a hydrostatic pressure of at least double the working pressure; the equipment to include all the necessary operating valves, a safety valve, two steam gauges, a gauge glass, and a steam heating coil for the generator.

The water sterilizers to consist of two tanks, each to be of full 25 gallons capacity. Each tank to be made from a tin-lined seamless, cold-drawn, brass or copper shell. The bottoms are to be made from brass castings, constructed for easy removal for cleaning the interior.

The filter to be provided, having valved connections to each tank, and valved connections to the raw water supply and waste lines. Filter casing to be made from copper or brass, and to be constructed so that the filter stone may be easily removed for cleaning.

Equipment to include for each tank all necessary operating valves, guage glass, safety valve, vacuum-breaking valve, thermometer, and a copper heating coil. One tank to be equipped with a water-cooling coil. By the use of suitable valves, the heating coil may be used for this purpose. Each water tank and the filter are to be subjected to a hydrostatic test of not less than double the working pressure.

The instrument and utensil sterilizers are to be constructed from copper. Instrument sterilizer of not less than 20 Stubs gauge; the utensil sterilizer of not less than 18 Stubs gauge. The edges of this receptacle to be well reinforced.

A tray of perforated sheet copper or brass is to be provided for each sterilizer; the tray to have strong side handles for lifting. The covers to be made from copper, preferably dome-shaped, and smooth on top.

A foot lift for raising and closing the covers only is to be provided. Each sterilizer to be equipped with a copper steam heating coil, and inside corner pieces or their equivalent to be provided which will separate the tray slightly above the heating coil. Each utensil


sterilizer to have steam, return, water, and waste valved connections to the supply lines. Each instrument sterilizer to have only valved steam, return, and waste connections to the supply lines.

The steam boiler to be a 6-horsepower, submerged-tube type, 100 pounds pressure standard boiler, equipped with suitable injector and 10 feet of stack with a damper in stack.
   The sterilizers are to be mounted each on a separate stand of suitable tubular steel construction. The arrangement to be such that, facing sterilizers, they will be placed in the following order from left to right: Water, utensil, instrument, and dressing sterilizers. They are to be placed as close together as conveniently possible, and piping is to be provided to connect all common valves, bringing the supply lines close together near the center of the outfit in the rear. The water and waste lines are to end with unions at the wall, situated approximately 12 inches back of the sterilizers. The steam and return pipes to be carried directly to the boiler (without a trap), which will be located approximately 10 feet in the rear of the sterilizers.

All valves to be Jenkins’s diamond pattern or equivalent, rough bodies. All water and waste pipes arid fittings to be galvanized iron and steam and return pipes and fittings to be black iron.

Exterior surfaces of all sterilizers to be finished in brush or satin nickel. The interior of all sterilizers to be tinned. Stands to be finished in aluminum bronze and a varnish finishing coat.

Each manufacturer shall furnish detailed installation plans and operating directions with each outfit.

The estimate for sterilizing apparatus, prepared in the Surgeon General’s Office and presented to the manufacturers at their meeting in Washington, D. C., April 11, 1917, called for 100 combination sterilizing outfits, delivery to be within approximately four months. Because of manufacturing requirements, the committee on sterilizers considered it essential that definite information concerning the quantity to be ordered be furnished at the earliest practicable date. Securing the needed materials was a slow process. The manufacturer of the seamless drawn shells required 60 to 90 days for delivery. The manufacturer of boilers required it was necessary that orders for sheets, castings, valves, and other parts be placed promptly.1 Because of lack of funds, purchases could not be made at that time and the placing of orders was delayed. The purchase of 30 sets of standard combination sterilizers for the base hospitals at the training camps was authorized May 25, 1917.2 The contracts were actually placed June 26. The number was equally distributed among five manufacturers, six outfits being purchased from each.

It soon became apparent that 30 outfits would be insufficient and more should be purchased. Instructions were issued August 3 for the purchase of 60 additional outfits.3 Contracts for them were placed August 9. The total number was distributed among the manufacturers according to their ability to produce them. The third authorization for the purchase of these outfits was issued November 16, 1917.4 It called for 75 outfits. They were distributed equally among the manufacturers. Subsequent instructions to purchase were issued from time to time thereafter as prospective needs indicated. The last instructions for purchase were dated August 13, 1918, for 100 outfits.5 The total number of standard outfits delivered during the war period was 338.6 The prices paid for the outfits were uniform for all manufacturers and rose steadily


throughout the period due to advances in the cost of boilers, boiler plate, and labor.

FIG.35.- Standard sterilizing outfit, with two sterilizers

The outfit originally authorized had but one dressing sterilizer, 16 by 36 inches in size. At the time this number and size were decided upon the contemplated capacity of the hospitals was 500 beds. It is doubtful that it would have been adequate for that number of beds. When the capacity of the hospital was increased to 1,000 beds, a single sterilizer of that size proved to be wholly inadequate for the needs of the hospital.7 The question then arose whether an additional sterilizer, 16 by 36 inches, should be furnished, making two of that size, or whether a larger size, 16 by 60 inches, should be substituted. The latter size required a track to carry the drums containing the dressings, and the shell was difficult to secure. The 16 by 36 inch shells were easy to obtain, and while two of then cost more than one of the larger size, they had greater capacity, did not require a track for the drums, and were more easily operated. Accordingly, it was decided to furnish two 16 by 36 inch dressing sterilizers for all 1,000-bed hospitals.8 An additional sterilizer was issued to all base hospitals in the United States. Two dressing sterilizers were included in the outfit provided for all base hospitals sent overseas. The appearance of the standard outfit with the two sterilizers is shown in Figure 35. The addition to the outfit of the second dressing sterilizer and certain other sterilizing equipment made


necessary a larger steam boiler. A 12-horsepower boiler was purchased with all the later outfits.9

Every base hospital established within the United States or sent overseas was equipped with a standard sterilizing outfit for surgical dressings. Sterilizing outfits for the training camps were delivered and installed by the time they were needed. The outfits required for the hospitals sent overseas were shipped usually with the other hospital equipment. The temporary general hospitals as they were opened were likewise equipped with standard outfits. The purchase of such outfits was based on known requirements, and deliveries were made in accordance therewith. For the most part the outfits were inspected at the factory and shipped direct to the designated hospital or port of embarkation. Only a few were carried in stock at any time.


A number of hospitals which came into being during the World War, as well as some already existing, had obsolete equipment that was expanded to larger capacity. The standard equipment was too large for them.10 A suitable outfit consisting of the same number of pieces as the original standard outfits, but of smaller size, was selected and purchased for them. Wherever there was space for a small boiler, steam-heated outfits were supplied. When space could not be provided for the boiler, and electric current was available, electrically heated outfits were supplied.11 If neither space for a boiler nor electric current was available, outfits of suitable size heated by blue-flame kerosene burners were furnished.

The need arose in the eye clinics and in the ear, nose, and throat clinics for a small water sterilizer and a small instrument sterilizer. A small unit mounted on a stand, consisting of a 3-gallon water sterilizer and a small instrument boiler, both electrically heated, was provided for this purpose. The issue of this unit was limited to hospitals where suitable electric current was available. The total number of the special outfits and electrically heated outfits supplied during the war period was 135. The aggregate number of sterilizing outfits delivered during the same period was 473.6


The Medical Department had become interested in portable disinfectors during the year preceding our entrance into the World War. In connection with the Mexican border mobilization in 1916, the need arose for these apparatus for disinfecting clothing and bedding. One manufacturer, in conjunction with an officer at the New York medical supply depot, developed such an apparatus. Eight of them were purchased and tried out on the border, where their merit was demonstrated. This disinfector consisted essentially of a disinfecting chamber 30 inches wide, 42 inches high, and 80 inches long, inside measurements, furnished with a basket type of car, extension tracks and supports, mounted on steel running gear and provided with a steam boiler of suitable size.12 The specifications for this apparatus appear below.13 The general appearance of the disinfector is shown in Figure 36.




To consist of an “American” Kinyouri-Francis jacketed disinfector, 30 inches wide by 42 inches high by 80 inches long, clear inside dimensions; a 6-horsepower submerged-tube vertical boiler, a water-storage tank, a complete set of firing tools and wrenches, and running gear.

FIG. 36.- Portable disinfector


Type. - Disinfector to be of the rectangular steam-jacketed construction, with 2-inch steam space between inner and outer shells.
Material. - Pressure shells to be of Otis, Carnegie, Cleveland Steel Co., or equal, 60,000 pounds tensile strength, open-hearth homogeneous flange steel plates ¼ inch thick. Victor rivets or equal. Castings for the end frames, saddles, etc., to be of semisteel or close-grained iron, as may be best suited for the purpose intended, to be free from blowholes, and all carefully machined where necessary to secure proper fitting of parts.
Riveting and stay bolting. - Longitudinal seam of inner shell to be single lap, riveted with 11/16-inch rivets, 2 ¼-inch pitch. Longitudinal seam of outer shell to be double lap, riveted with 11/16-inch rivets, 2 ¼ -inch pitch. Girth seams to be single lap, riveted with 11/16-inch rivets, 2 ¼-inch pitch. Rivet holes to be punched or drilled, and all unfair holes to be brought into line by the use of reamer; no drift pins to be used. Shells to be stayed with 7/8-inch stay bolts of selected, double-refined iron, spaced approximately 6 inches between centers, thereby making jacket surrounding chamber amply strong for full 100 pounds working pressure. All seams to be carefully calked and made perfectly tight.

Bottom plate at front to be reinforced and to form a unit with front truck by means of a fifth wheel and king pin. On each side at rear shall be a heavy cast-steel or malleable


bracket bolted into a riveted reinforcing steel plate saddle, supporting boiler and forming riding supports for the disinfector-boiler combined units.

Door. - To be of 7/16-inch flange steel, properly dished, fitted to one end of disinfeetor, and closing against a ¾ inch Ebonite, or equal, gasket loaded in groove turned in face of cast end frame and a steam and vacuum-tight joint made by a series of not less than 16 radial crucible spring steel, taper-turned, arms or levers engaging the rim of said end ring at outer ends and being connected to a central disk by a ball-and-socket joint and forced outward by the rotation of handwheel carrying said disk. The door to swing on a heavy forged-steel davit, carefully fitted to the end frame and provided with means for accurate adjustment. To minimize friction and facilitate operation, improved ball or roller bearings to he used in the construction of door and davit.

Rear head. -
Tobe jacketed, consisting of two flanged steel heads, ¼- inch thick, with 2 inch steam space between. To be braced with 7/8 inch stay bolts about 6 inches center to center.

. - All to be of best quality steel, carefully riveted and calked to insure perfect tightness under both steam and vacuum.

Test. - The jacket to be tested and made perfectly tight under a hydrostatic pressure of 150 pounds per square inch, and again tested at 100 pounds steam pressure in the jacket and at not less than 30 pounds steam pressure in the chamber for a working pressure of 12 to 15 pounds per square inch.

Piping. - To provide for:
1. Entrance of high-pressure steam to jacket.
   2. Entrance of low-pressure steam through pressure-reducing valve to chamber directly on top near each end.
3. The escape of air from chamber and the circulation of steam within chamber to facilitate the process of disinfection.
4. High-pressure steam connection to improved type of ejector of sufficient capacity to create and maintain a vacuum of not less than 20 inches with 80 pounds of steam at apparatus.
5. The condensation from inner chamber to run free from bottom at front end, controlled with a valve.
6. The condensation from jacket from center of bottom to be connected to improved pipe expansion trap and discharged into feed-water tank for use in boiler. To be controlled also with a valve.

Fittings. - To include, in addition to piping specified, all necessary valves for the proper control of steam to both jacket and chamber, compound pressure and vacuum gauge for chamber, pressure gauge for jacket, low-pressure safety valve set at from 12 to 15 pounds for chamher, highs-pressure safety valve for the jacket set at from 60 to 100 pounds as preferred, one pressure-reducing valve, one air ejector, one steam trap, and all necessary connections. All to be guaranteed to he satisfactory for the purpose intended.
Casting. - All piping and fittings, except that on bottom of disinfeetor for condensation, tank, and formaldehyde-ammonia generators, to be located on top and covered in a sheet-steel casing, hinged and provided with a suitable lock.
Formaldehyde-ammonia generators. - Disinfector shall be provided and fitted with the “American” improved type vacuum formaldehyde-ammonia generators, consisting of two containers and one gas generating chamber, all complete, properly valved and connected te disinfecting chamber.
Car. - To be of wrought-steel construction, basket type, mounted on roller wheels and furnished with, track and truck supports necessary for operation in approved manner, unless otherwise ordered.
Finish. - Interior of chamber, also car frame and wheels, to be painted three coats of aluminum bronze; exterior to be painted three coats of gloss black, unless otherwise specified in order. A substantial, removable, sheet copper hood to be furnished and fitted inside at top of chamber and properly supported.



Boiler to be of the vertical submerged-tube type, 30 inches in diameter by 5 feet 8 inches high. Shell to be ¼- inch thick, open-hearth steel; the heads of 3/8-inch flange steel. To be fitted with 50 tubes, 2 inch diameter and built to carry a working pressure of 100 pounds per square inch. Smoke pipe of 13 inch diameter, to be hinged for lowering when not in use.

Boiler to be fitted with ash pan formed by extension of shell, with bottom of No. 8 steel, and to be complete with all fixtures, including safety valve, injector, steam and water gauges and cocks, blow-off cock, together with all piping to connect with disinfector.

Boiler to be secured to and made self-contained with disinfector by heavy cast-steel or malleable plates bolted to reinforcing saddles to support boiler at proper location. Firing tools, consisting of hoe, slice bar, and scoop to be provided.


These shall be constructed to support the imposed weight at three points, one in front and two in the rear. The forward truck to be provided with steel roller-bearing wheels not less than 2 inches in diameter and ¾ by 6 inch face. The framework to support a steel fifth wheel forming a unit with the bottom of the disinfector. Heavy steel leaf elliptical springs to be underslung to not less than 2 inch square axle. To be provided with removable tongue, two steel strap eyes for attaching tractor, double trees, and chains. The rear wheels to be steel roller-bearing, 48 inch diameter and not less than ¾- by 6 inch face on not less than a 2 ½-inch square steel axle.

The heavy cast-steel or malleable plates supporting the overhanging boiler to the disinfector are also to form the riding supports; at points of contact heavy steel helical springs to be provided. A single driver’s seat shall be placed on top of disinfector.

The wheels, axles, and woodwork to be finished in Indian red paint, varnished. The disinfector and boiler in black machinery enamel.

Erie, Pa.

In considering the needs of base hospitals in the American Expeditionary Forces, it was foreseen that there would be times, during and just after active military operations, for example, when the surgical sterilizing apparatus would be inadequate. It was thought that portable disinfectors might be used in such emergencies. Furthermore, since evacuation hospitals were not supplied with surgical dressings sterilizers, the portable disinfector might be very useful to them on such occasions as those referred to above. In order to determine their efficiency for that purpose and before making recommendations for their use under such conditions, tests were made early in March, 1918, by an officer detailed from the laboratory of the Army Medical School. The results of those tests are quoted here in full:14


The test was made to determine whether all infectious organisms in bedding, clothing, or surgical dressings would be killed; in other words, to determine the reliability of this type of disinfector as a sterilizer.

The organisms used were Staphylococcus aureus and B. subtilis. The Latter is not pathogenic, but is quite as difficult to kill as anthrax or tetanus and could be carried more easily. The material used in the test was prepared as follows: Forty-eight hour broth cultures were prepared. Stained smears indicated that the culture of B. subtilis contained many spores. Small pledgets of gauze were then prepared and soaked in these cultures. The gauze pledgets were about an inch in length, by one-fourth of an inch wide, and consisted of several layers of gauze sewed together. After they had been thoroughly saturated


in the culture, they were removed to a sterile Petri dish and dried at room temperature, and wrapped in sterile containers for use.

The method of experiment was as follows: Several of these infected pledgets of gauze were buried in different packages of gauze dressings. These packages of dressings were then placed in different parts of the disinfector in the middle of folds of blankets or under mattresses, etc., and the disinfector was filled entirely with old blankets, clothes, packages of surgical dressings, and cotton waste, so as to simulate service conditions as closely as possible. Self-registering thermometers and Diack controls were also buried in the same gauze packages with the cultures so that the temperature reached could be accurately recorded. At the end of the period of exposure the packages were opened, and the infected pledgets of gauze were dropped by sterilized forceps into tubes of sterile broth. Controls were made by planting a number of pledgets of infected gauze that had not been passed through the disinfector, in tubes of bouillon. All of these control tubes showed growth on the following morning, proving that the cultures of staphylococcus and B. subtilis were both alive and viable. The results of the tests made are as follows:


Steam was up and the apparatus already warmed; 65 pounds pressure in the jacket. A vacuum of 16 inches was obtained in four minutes. Steam was then introduced into the cylinder, and the contents were given a 20-minute exposure at 15 pounds pressure.

A package of gauze was buried at the bottom in a mattress, and contained pledgets infected with Staphylococcus and B. subtilis, and also a Diack control. After the exposure, a vacuum of 8 inches was produced and the chamber opened. When removed after the test, the Diack control was melted, indicating a temperature at least 250 o F. and the infected pledgets were cultured. All were sterile.

A second package of gauze was placed in the middle of the disinfector, buried in a closely packed package of blankets. A self-registering thermometer was also in the package. At the end of the exposure the pledgets of infected gauze were placed in bouillon tubes, and no growths occurred in any tube. The thermometer registered 255 o F.


With 65 pounds pressure in the jacket, a vacuum of 18 inches was obtained in four minutes, steam was introduced into the chamber, and the bedding and clothing exposed for 30 minutes at 15 pounds pressure. At the end of the exposure a vacuum of 9 inches was produced, and the chamber was opened five minutes after the exposure.

A package of gauze with infected pledgets and thermometer was buried in a mattress at the bottom. At the end of the test the thermometer registered 231o F. The pledgets were cultured, and all remained sterile. No growth occured in any tube either of staphylococcus or B. subtilis.

A package of gauze was buried in blankets in thie middle as before. The thermometer in this package registered 250o, a Diack control similarly placed was not melted, but cultures of the infected pledgets all remained sterile.


With 65 pounds in the jacket, 18 inches of vacuum were obtained in four minutes. Steam was introduced into the cylinder and an exposure of 40 minutes was given at 15 pounds pressure. At the end of the experiment, 9 inches of vacuum were produced and the chamber was opened in five minutes from the termination of the exposure.

One package of gauze was buried in the middle of the cylinder as before, with infected pledgets, three therlnorneters, and a Diack control. When the package was removed after the exposure, the Diack control was melted, but all three thermometers registered 247 o F. It is thus seen that the Diack control, which is supposed to melt at 250 oF. is not an accurate method of measuring temperature, for in one case one failed to melt although the


thermometer registered 250, while in another ease the control melted although three thermometers agreed on a reading of 247o F. All pledgets were cultured and no growth occurred in any tube.

One package was buried in the bottom as before, with pledgets of gauze. These were cultured at the conclusion of the exposure, and all tubes remained sterile.


A test was made of the sterilizing power of the formaldehyde apparatus. As it is notoriously difficult to secure penetration with formaldehyde, and as the cylinder was closely packed as in all other tests, it was believed that this test would afford a demonstration as to the penetrating power of formaldehyde when used in this disinfector with a vacuum. At the same time it must be stated that as heat was used through the steam in the jacket, and as the bedding necessarily contained some moisture as the result of its passage through the previous tests, these circumstances alone may have been sufficient to cause sterilization.

With 65 pounds of steam in the cylinder, a vacuum of 20 inches was produced in six minutes. Seventeen ounces of formaldehyde solution (100 parts 40 per cent formaldehyde, 10 parts glycerine, and 20 parts calcium chloride) were introduced in vapor into the cylinder in four minutes. After the formaldehyde was vaporized there was still 15 inches of vacuum in the chamber. An exposure of one hour was given, at the end of which time the guage showed that there was still 4 inches of vacuum. This was increased to 10 inches, and 8 ounces of ammonia were introduced to neutralize the formaldehyde, and the disinfecter was opened. No fumes of formaldehyde were noticeable.

Three packages of gauze were used in this test:

The first package, with infected pledgets was placed on top of the bedding where the gas would have free access to it. Two thermometers that were hung near this package registered 295o and 300oF., respectively. This was the temperature in the open, and it is not to be supposed that the temperature in the mass of bedding was as high as this. At the end of the exposure, the infected pledgets were cultured and all remained sterile.

A package of gauze was buried in blankets in the middle of the mass of clothing as before. The infected pledgets removed from this package after exposure were cultured and all cultures remained sterile.

A package was also buried in the mattress at the bottom as before. The infected pledgets removed from this package after exposure were cultured and all remained sterile.

From the above tests, the conclusion is drawn that when properly operated, this disinfector is an efficient sterilizer even when the cylinder is closely packed with clothes or dressings. Every culture placed in the disinfeetor was killed whether the exposure was 20, 30, or 40 minutes. It is believed, therefore, that a 20-minute exposure can be recommended, and as it takes approximately five minutes at the beginning to introduce the steam and another five minutes at the end to create the vacuum and remove the steam so that the clothes may be dry when removed, this 20-minute exposure will actually require 30 minutes. It will thus be seen that two loads may be sterilized in an hour. In other words, it could be relied on to sterilize the clothes of about two companies an hour.

The formaldehyde sterilization, using a temperature of about 90o F., which will not injure leather, can certainly be relied upon to sterilize leather articles and such articles of equipment as may be destroyed by steam, and where great penetration is not required. This is probably all that will be required of the formaldehyde process. At the same time, it may be stated that this process may be capable of penetration because of the effective vacuum that can be created by the apparatus, and in the test described above there were indications, in change of color and appearance of certain articles, that the formaldehyde had actually penetrated to the interior of the mass used in the experiment.

While unfortunately no lice or bedbugs were available for test, it is certain that any process that will kill the spores of B. subtilis will kill these insects, which are sensitive to heat, and the apparatus is therefore to be recommended as an efficient apparatus for the delousing of a command.


Mr. J. E. Hall, the president of the American Sterilizer Co., states that in 30 days’ time they can turn out this portable disinfector at the rate of one a day.

Lieutenant Colonel, M. C.

Because of the reported prevalence of vermin among the troops in France, the question arose as to the best manner of disinfecting the clothing of the body louse and its eggs. The use of cyanide gas as a disinfectant was proposed.15 It was understood that it would take approximately 45 minutes exposure to the gas to destroy the body louse and its eggs. Even then it was doubtful that the eggs would be destroyed. Having in mind the fact that vermin of all sorts are comparatively readily destroyed by heat, it was thought that the portable disinfector might prove effectual for that purpose. To determine its value for this service, the following tests were made:16


Inasmuch as active lice are more easily killed than nits, the time required effectually to delouse clothing is the time required to kill the nits. Through the courtesy of the Bureau of Entomology of the Department of Agriculture, I was supplied with 160 nits of Pediculus humanus vestimenti, deposited from July 2 to July 5, inclusive. Under proper conditions they would have hatched from July 9 to July 16, inclusive. Those conditions (of body heat and humidity) were not supplied until after some of the nits had been subjected to the action of the disinfector. The exposures were made on July 13 in the forenoon and were as follows:

Forty-six nits were exposed for five minutes. During this time the maximum temperature within the chamber was 250 o F. The maximum temperature within the bundle in which the nits were wrapped was 192o F. The bundle was made up of old underwear, packed medium tight, arid measured 14 ½- inches long and 7- inches in diameter.

Thirty-four nits were exposed, similarly wrapped, for 10 minutes. The maximum temperature in the chamber during this period was 257o F. The temperature within the bundle was not taken, but it is probable that inasmuch as the period of exposure was twice as long as before, the penetration was more complete.

Thirty-five nits, similarly wrapped, were exposed for 20 minutes. This time the temperature within the chamber reached 266o F. The temperature within the bundle was not recorded.

Forty-five nits were kept as controls, and these, of course, were not subjected to the action of the disinfector at all.

Each group of nits was then encased in a Bacot entomological box and the boxes, placed in small cotton bags, were worn beneath the undershirt. Within 24 hours some of the 45 control eggs had hatched. On July 19 no more had hatched. The others may be considered as dead. Hence, the mortality of the control nits is 23 per cent.

To date, July 22, none of the exposed eggs has hatched.

These data are presented concisely in Table I.

TABLE I.- The destruction by steam of the nits of Pediculus humanus vestimenti by means of the Hartsock model, “American” Kinyoun-Francis steam and formaldehyde portable disinfector


These experiments seem to indicate that nits exposed to the action of steam under 15 pounds pressure in the Hartsock model, “American” Kinyoun-Francis steam and formaldehyde disinfector, even when well covered with several thicknesses of underclothing, are killed within five minutes.

It is probable, therefore, that exposure for 10 to 15 minutes in this apparatus will be more than sufficient effectually to delouse clothing.

The question of disinfectors was presented to the committee on sterilizers at their meeting in Washington in April, 1917.1 The number and type of disinfectors had not been clearly determined at that time. For a fixed hospital it was thought that the stationary type would be satisfactory and probably preferable; the portable type would have a wide field of usefulness, both in camps in the United States and overseas. The first instructions for the purchase of portable disinfectors was issued June 21, 1917, and called for 12.17 The next instructions were issued at the end of August, 1917, and called for 28.18 The number of portable disinfectors authorized for purchase during the period June, 1917, to December, 1918, inclusive, appears in the following table, showing dates and firms from which purchased: 19



Sterilizers - Continued

Calls for these portable disinfectors steadily increased. The output by the firms already mentioned was limited. New sources of supply were sought in October, 1918. Several manufactures of boilers were approached with a view of interesting them in the manufacturers of these disinfectors. Only firms known to have the facilities for the manufacture of such apparatus and to be financially sound were included in this survey of facilities. Some of the firms interviewed were capable of producing only the steam boilers, while others were able to produce the entire outfit. Several of the firms found to be interested were furnished blue prints and specifications for consideration and to determine their ability to produce the outfits.20 Fortunately, the cessation of hostilities terminated the need for disinfectors before it became necessary to place orders in addition to those already enumerated.



Portable disinfectors, being bulky, were purchased in accordance with a definite schedule of requirements. It was not contemplated that they would be stored at any point longer than was necessary to make the distribution required. A number of them were distributed among the training camps within the United States, but the bulk of them were intended for use overseas. One of the base hospitals sent to France in July, 1917, was provided with one of these disinfectors. Its use and advantages were promptly appreciated.21 A request was cabled to the Surgeon General, August 16, for 15 of them.22 Instructions were given that 5 be shipped at once to the medical supply depot in France. They arrived at the port of embarkation by the end of August and were promptly floated. The chief surgeon, A. E. F., was advised that 5 disinfectors would be shipped at once and the remainder as soon as available.23 Instructions were issued November 5 for the shipment of 10 portable disinfectors in addition to the 5 ordered shipped in August.24 Thereafter shipments were made direct from the manufacturers to the ports of embarkation as the apparatus became available. The number shipped steadily increased. In the month of October, 1918, 37 were floated, making a total of 146 shipped to France.25 Water transportation was insufficient to take care of the full requirements for that month, which were 60.25 The following table shows the rate of delivery by months during the calendar year 1918: 26

Disinfectors, portable steam


Many of the pieces of apparatus, both of the standard sterilizing outfit and the portable disinfectors, were lost, broken, or damaged in transportation to France.27 Spare parts were necessary to replace these broken or damaged parts, and a list of needed parts was prepared in July, 1918.28 The number of these spare parts shipped from month to month was increased with the number of sterilizing outfits and disinfectors overseas. In preparing these lists the different manufacturers of the outfits were requested to furnish a list of the parts which they had replaced in the past and the relative proportions of each required.28



For fixed hospitals which were likely to be permanent after the end of the war, it was considered expedient to furnish stationary types of disinfectors instead of the portable type. The chambers of these disinfectors, as a rule, were approximately the same size as that of the portable outfit, but variations were made according to the requirements of the individual hospital. A number of the stationary disinfectors were purchased.


(1) Letter from the chairman, committee on bed, clothing, and miscellaneous hospital supplies, to the War Department, Office of theSurgeon General, May 11, 1917, transmitting a report and recommendation of the special committee on sterilizers. On file, Finance and Supply Division, S. G. O., 14636-13-1.
(2) Letter from the Surgeon General to the officer in charge, Medical Supply Depot, New York, May 25, 1917. Subject: Supplies for a million men. On file, Finance and Supply Division, S. G. O., 14039-20-14.
(3) Letter from theSurgeon General to the officer in charge, Medical Supply Depot, New York, August 3, 1917. Subject: Steam sterilizing outfits. On file, Finance and Supply Division, S. G. O., 14039-20-14.
(4) Letter from theSurgeon General to the officer in charge, Medical Supply Depot, New York, November 16, 1917. Subject: Purchase of disinfectors and sterilizing outfits. On file, S. G. O., Finance and Supply Division,  713-359/257.
(5) First indorsement from the Surgeon General’s Office to the officer in charge, Medical Supply Depot, New York, August 13, 1918, relative to the purchase of 100 sterilizing outfits. On file, Finance aud Supply Division, S. G. O., 713-359 N.Y./886.
(6) Quantities of deliveries of combining sterilizing outfits, U. S. Army pattern, delivered January 18, to December 31, 1918, compiled in the Surgeon General’s Office in 1918. On file, S. G. O., Finance and Supply Division,  531 Misc./154.
(7) Letter from the medical supply officer, U. S. Army, New York, to theSurgeon General, November 22, 1917. Subject: Sterilizing sets. On file, Finance and Supply, Division, S. G. O., 713-539  N. Y. D./276.
(8) Third indorsement from Lieut. Col. E. B. Vedder, Army Medical School, to the medical supply officer, Ne\v York City, December 6, 1917, relative to the most suitable sizes of dressing sterilizers. On file, Finance and Supply Division, S. G. O., 713-539 N. Y. D./276.
(9) Sixth indorsement from the medical supply officer, New York, to theSurgeon General December 20, 1917, relative to the size of horsepower boilers supplied with sterilizing outfits On file, Finance and Supply Division, S. G. O., 713-539 N.Y.D./276.
(10) Letter from the department surgeon, Northeastern Department, Boston, to the Surgeon General, February 7, 1918. Subject: Hospital facilities. On file, Finance and Supply Division, S. G. O., 188-80 D. S. B./33.
(11) Letters from the Surgeon General to the officer in charge, Medical Supply Depot, New York City, March 18, 1918. Subject: Steam sterilizers and sterilizing outfits. On file, Finance and Supply Division, S. G. O., 188-80 D. S. B./33.
(12) Letter from theAmerican Sterilizer Co., Erie, Pa., to Col. H. C. Fisher, War Department, June 27, 1917, relative to portable disinfeetors. On file, Finance and Supply Division. S. G. O., 28 A.S.C./40.


(13) Letter from the American Sterilizer Co., to Col. Edwin P. Wolfe, M. C., July 22, 1926, relative to portable disinfectors. On file, Finance and Supply Division, S. G. O.,  28 A. S. C./40.
(14) Letter from the Surgeon General to the Chief surgeon, A. E. F., France, March 23, 1918. Subject: Portable disinfectors. On file, Finance and Supply Division, S. G. O.,  28 A. S. C./13.
(15) Letter from the officer in charge, Medical Supply Depot, New York, to the Surgeon General, June 26, 1918. Subject: Request for the services of bacteriologists. On file, Finance and Supply Division, S. G. O., 713-539 N. Y./796.
(16) Letter from First Lieut. Joseph W. Smith, Jr., M. C., to the Surgeon General, U. S. Army, July 20, 1918. Subject: Investigation of disinfector. On file, Finance and Supply Division, S. G. O., 713-539  N. Y./796. 
(17) Letter from the Surgeon General to the officer in charge, Medical Department, New York, June 21, 1917. Subject: Disinfectors. On file, Finance and Supply Division, S. G. O., 14039-107.
(18) Letter from the Surgeon General to officer in charge, Medical Supply Depot, New York August 18, 1917. Subject: Portable disinfectors. On file, Finance and Supply Division, S. G. O., 713-539/34.
(19) List of disinfectors, portable, steam, purchased during the World War, compiled from official records in the Surgeon General’s Office.
(20) Letter from the officer in charge, Medical Supply Depot, New York, to the Surgeon General, November 16, 1918. Subject: Portable disinfectors. On file, Finance and Supply Division, S. G. O., 713-539 N. Y./1110.
(21) First indorsement, chief surgeon, Base section No. 1, to chief surgeon, Lines of Communication, A. E. F., October 14, 1917. Subject: Steam disinfectors. On file, Finance and Supply Division, S. G. O., 713-250/2.
(22) Paragraph 15. Subject: Paragraph 1, Cable 102, H. A. E. F., Paris, to The Adjutant General, August 16, 1917, relative to steam sterilizers. On file, Finance and Supply Division, S. G. O., 713-250/2.
(23) Cable from the Adjutant General to the Commanding General, H. A. E. F., August 20, 1917, relative to shipment of disinfectors called for on Cable No. 102, H. A. E. F. On file, Finance and Supply Division, S. G. O.,  715-250/2.
(24) Eighth indorsement, Surgeon General’s Office to officer in charge, Medical Supply Depot, New York, November 15, 1917, directing shipment of portable disinfeetors. On file, Finance and Supply Division, S. G. O., 713-250/2.
(25) Memorandum for Col. E. P. Wolfe, M. C., from Capt. Fred. J. Murray, U. S. A., October 30, 1918, relative to shipment of portable disinfectors to France during 1918. On file, Finance and Supply Division, S. G. O.
(26) Number of disinfectors, portable, delivered in 1918, compiled in the Surgeon General’s Office, 1918. On file, Finance and Supply Division, S. G. O.,  531-Misc./154.
(27) Letter from the chief surgeon, A. E. F., to the Surgeon General, April 16, 1918. Subject: Damaged disinfectors in transit. On file, Finance and Supply Division, S. G. O. , 250 France/340.
(28) Letter from the Surgeon General to the officer in charge, medical supply depot, Nesv York, July 11, 1918, relative to spare parts for sterilizers for overseas shipments. On file, Finance and Supply Division, S. G. O., 713-539 N. Y./814.