size and pattern should be equally efficient, but practical experience shows that no safe prediction of the 'functioning capacity' of any apparatus can be given before a thorough test has been made. <Callout type="important" title="Testing is crucial">Always conduct thorough tests on new disinfectors.</Callout> HENNEBERGS DISINFECTOR. (Zeitschrift f. Hygiene, Bd. I, Hft. 2.) This apparatus consists of two superimposed cylinders, of which the upper (Fig. 1,0) is intended to receive the articles to be disinfected, while the lower (g) is the boiler in which the steam is generated. The upper cylinder has double walls and a cover of tin. The interspace between the outer and inner walls is filled with some non-conducting material. <Callout type="gear" title="Non-conductive Material">Ensure your apparatus uses an appropriate insulating material.</Callout> The lower end of the cylinder is open, and rests in a groove which forms the upper end of the boiler. When this groove is filled with water, the joint between the re- ceptacle and boiler is perfectly tight and does not permit the escape of steam. The walls of the boiler are corrugated to increase the heating surface. A perforated iron plate (/') forms the lid of the boiler. <Callout type="risk" title="Steam Pressure">Be cautious with pressure; it can be dangerous if mishandled.</Callout> The fire, heating the upper portion of the iron sides of the boiler, prevents Fig. 1. condensation of the steam first disengaged, and at the same time aids in drying the materials to be disinfected, and expelling the air in the upper cylinder before the latter becomes filled with steam. The steam evolved at the surface of the water is also superheated in passing over the heated surfaces of the sides of the boiler. <Callout type="tip" title="Superheat Steam">Ensure your apparatus superheats steam for better disinfection.</Callout> The steam is not confined under pressure, but is allowed to escape through the duct (6) which may lead directly to the open air or into a chimney. At the lower end of the escape pipe a thermometer is attached which registers the temperature attained in the chamber. To charge the disinfector, the upper cylinder is raised a short distance by means of an ingenious mechanism, until clear of the groove in which its lower end rests. The cylinder is then turned on its side until it rests almost horizontally. It is fixed in this position until the articles to be disinfected have been placed in it, enclosed in a wire basket. <Callout type="beginner" title="Wire Basket">Use a wire basket for better air circulation and disinfection.</Callout> The cylinder is then again turned upright, sunk into its proper groove, and the fire started. After the steam has passed a sufficient length of time to make sure of thorough disinfection, a valve (k) is opened which leads into the chimney. The strong draught not only causes the steam now produced to pass into the chimney, but also draws out that in the cylin- der. In a few minutes the contents of the disinfector are entirely dry, and can then be removed by turning the cylinder on its side, as in the process of charging. The other, non-essential, parts of the apparatus are pipes for filling and emptying the boiler, and for removing the condensed vapor. <Callout type="important" title="Regular Maintenance">Maintain your equipment regularly to ensure it functions properly.</Callout> The estimated expense of running this apparatus, including interest on capital invested, is 8.90 marks (about $2.10) per day for a machine of sufficient size to disinfect 7.35 cubic meters (about 250 cubic feet) of mate- rials. The disinfecting power of the apparatus has been tested by Dr. E. Esmarch, and found to meet all requirements. W. Budenberg, a manufacturer of disinfecting apparatus in Dortmund, exhibited a model of a new disinfector at the last meeting of the German Association of Naturalists and Physicians. No description was pub- lished, but the following points are of some interest. The steam is under slight pressure. <Callout type="warning" title="Pressure Hazards">Be cautious with pressurized systems; they can be dangerous.</Callout> The apparatus is easily transportable, and can be readily connected to any steam generator. After the steam begins to enter the disinfecting chamber, a temperature of 1050 C. (2210 F.) is secured in five minutes, and after five minutes longer the temperature in the interior of large packages is raised to io2°-io3° C. (2i6°-2i8° F.). A bacteriological test showed complete destruction of spores. An apparatus 2.25 meters (7 ft. 4 in.) long, nine tenths of a meter (35 inches) broad, and 1.50 meters (4 ft. 11 in.) high, can be made for 400 marks ($100). COST OF DISINFECTION IN BERLIN. H. Merke gives in the Deutsche Vierteljahresschrift fur Offentliche Gesundheitspflege, Bd. 19, Hft. 2, some interesting details concerning the management and expense of the public disinfecting station in Berlin. The station was opened for the use of the public on November 1, 1886 ; and in the two months, November and December, 1886, 327 persons made use of the apparatus for purposes of disinfection. <Callout type="important" title="Public Use">Public stations can be effective but may have limitations.</Callout> The materials to be disinfected occupied a total space of 722.4 cubic metres (25,284 cubic feet). In 298 of the 327 applications, the disease for which disinfection was requested was ascertained. In the remaining 29 cases, either the diagnosis could not be learned, or the materials disinfected consisted of rags, furniture, or trimmings of sleeping-cars, or articles from places suspected of being infected. In these cases the disease to which the arti- cles were supposed to have been exposed was generally cholera. REPORT OF COMMITTEE ON DISINFECTANTS. 211 Disinfection was practised in the 298 cases in which the disease was known, — After diphtheria in 122 cases, or 40.93 per cent. <Callout type="risk" title="Disease Spread">Be cautious with suspected items; they may still pose a risk.</Callout> After suspected cholera in 23 cases, .... or 7.72 per cent. After consumption in 47 cases, or 15.77 per cent. After scarlet fever in 34 cases, or 11.40 per cent. After typhoid fever in 11 cases, . . . - . . or 3.60 per cent. After syphilis, scabies, and other skin diseases in 61 cases, or 20.47 Per cent. Curiously, the larger proportion of those desiring disinfection belonged to the better classes. Of the applications, 28.6 per cent, were from merchants. 13.4 per cent, were from mechanics. 11.4 per cent, were from professional men. 9.0 per cent, were from officials. 5.7 per cent, were from manufacturers. 4.0 per cent, were from rentiers. 3.0 per cent, were from officers. 5.7 per cent, were from laborers. 19.3 per cent, were from restaurateurs, etc. The charges for disinfection are four marks ($1.00) per cubic meter, including bringing and returning the articles. Where rags are disinfected, the charges are one mark (24 cents) per 100 pounds, exclusive of transportation to and from the disinfecting establishment. <Callout type="important" title="Cost Considerations">Understand the costs involved in public disinfection.</Callout> The materials disinfected consisted of 12,935 different articles, classi- fied as follows : Clothing 1,710 pieces. Body linen 5,351 pieces. Feather beds i>940 pieces. Mattresses and bolsters 1,084 pieces. Straw sacks 20 pieces. Furniture 101 pieces. Other articles, such as carpets, sacks of rags, curtains, spreads, etc., 2,729 pieces. NEW ELECTRICAL REGISTERING THERMOMETER. Fig. 2. Merke has also devised a new electrical contact thermometer for use in determining the temperature of the interior of the disinfecting appa- ratus. It is constructed as follows : An ordinary wooden spring clamp (Fig. 2) is faced at the clamping end {a a) with metal strips (c c) . The other end (6 b) is armed with small strips of metal with two equal-sized openings or rings (d d) upon each arm of the clamp. In pressing to- gether this end of the clamp the rings should exactly dovetail into each other. Through the short tube thus formed by the rings, a small rod of fusible metal, made by melting together 8 parts of bismuth, 3 parts of lead, and 3 parts of tin, is inserted. This constitutes the thermometer. To the metal facings of the other end of the clamp conducting wires are attached, which connect it with an electrical alarm bell. The wires are kept from getting entangled in the clamp by a square block of wood (_/"), to which the wires are attached. The whole apparatus is now enclosed in a hollow wooden capsule, with numerous openings in its sides to per- mit access of steam, and placed in the centre of the package of articles to be disinfected. When the temperature in the centre of the package, or around the thermometer, reaches ioo° C. (2i2°F.), the metal rod melts, the spring comes into play and closes the clamp. The two metal surfaces (c c) coming in contact close the circuit, and the electric bell rings to indicate the temperature. This thermometer is cheap, and not liable to get out of order. By placing a number of them in different parts of the disinfecting apparatus, and connecting each one with an electric circuit, the exact time at which the temperature of ioo° C. is reached in each portion of the apparatus can be exactly determined. This contact thermometer can also be used without the electric circuit. If introduced with the articles to be disinfected, and the rods are found to have been melted after exposure, it indicates that the temperature of ioo° C. has been reached. <Callout type="tip" title="Temperature Monitoring">Use multiple thermometers for accurate monitoring.</Callout> DISINFECTION BY CHEMICAL AGENTS. In the latest instructions issued by the Berlin health authorities, all disinfectants are discarded except heat and carbolic acid. The latter is used in five per cent, solution for fecal and urinary excreta, expectora- tion, nasal discharges, etc., and in two per cent, solution for articles of clothing, bedding, and wiping cloths used about the sick-room. These articles are directed to be soaked for twenty-four hours in the two per cent, carbolic acid solution, then boiled for half an hour, and afterward washed in water with half an ounce of soft soap to the gallon. Leather articles (boots, shoes, etc.) are washed in five per cent, solution of car- bolic acid. Articles which cannot be washed are sent to the public dis- infecting station for disinfection; or, if of little value, are destroyed by burning. To the great surprise of many sanitarians, bichloride of mercur- ry and chloride of lime are not mentioned in the Berlin instructions. In Boston, mercuric bichloride is generally used as a disinfectant. Dr. S. H. Durgin, a member of the committee on disinfectants and chair- man of the board of health of that city, uses a solution of the strength of one part in 3 : 4000 for spraying the streets. A bag of the salt is hung inside of the street watering-carts, and as it dissolves the water is impreg- nated with the disinfectant. The rapidity of solution of the salt is regu- lated by the thickness of the wraps placed around it. The capacity of the water-tank and the number of times it is filled during the day, to- gether with the weight of the mercuric bichloride, give the data for find- ing the strength of the solution. In Chicago, the solution of the bichloride is freely used in yards, cel- lars, gutters, etc. Watering-pots with fine sprinklers are used to scatter it over the surfaces where it is required. Guttmann and Merke have studied the methods of disinfecting apart- ments after infection by infectious diseases. Many experiments were made, using a five per cent, solution of carbolic acid and a 1 : 1000 solu- tion of mercuric bichloride. The latter was found to be the most effi- cient, and always trustworthy. <Callout type="risk" title="Mercury Exposure">Be cautious with mercury; it can be harmful.</Callout> The method decided upon as the best is the following: The floor of the room is first saturated with a solution of mercuric bichloride (1 : 1000), and then a spray of the same solution directed against the walls and ceiling until these are thoroughly moist- ened, which is manifested by the formation of small drops. The floor is then mopped dry, and afterward washed up with clean water. Finally, the walls and ceiling are again sprayed with a one per cent, solution of soda. This causes the formation of oxychloride of mercury, which is brushed off when dry. By this subsequent treatment, all danger of mer- curialization of the occupants of the room is removed. The proceeding seems to be rational, cheap, and more efficient than any other hitherto used. Herasus and Kreibohm experimented with volatilized mercuric bichlo- ride and sulphur in combination (following one fumigation by the other), but failed to secure disinfection of the walls and contents of the room. The method seems to be untrustworthy, and to have nothing in its favor. The method of disinfecting the bilge of ships has been studied by Koch and Garfky. A solution of mercuric bichloride was employed, using a sufficient quantity to produce the copper reaction when thoroughly mixed with the bilge water. At the end of eighteen hours the disinfection was complete, as shown by bacteriological tests. The solution is poured into the bilge, and a thorough mixing secured by pumping. No injury re- sults to the ship or her occupants from this treatment. The pump used becomes ' infected ' with mercury, however, and should not be employed afterward for pumping water for drinking or domestic purposes. This caution, which is given by the authors, seems hardly necessary, as no one would think of drinking bilge water under any circumstances, and the bilge pump is generally a fixture on vessels. The disinfection of stables is an important part of the prophylaxis of the contagious diseases of animals. Dr. Hugo Plaut, of Leipzig, recom- mends the following procedure : A wooden structure equally divided into two apartments by a partition is to be built before the main stable door. A door is placed in the partition wall, allowing communication between the two apartments, and one door is to open externally. The outer apartment serves as a receptacle for the clothing worn outside of the stable, while the inner one contains the stable dress. When the attendant enters, he undresses in the outer apartment, then passes through the communicating door into the inner apartment, where he dresses in the stable clothes. When he leaves the stable, he removes his stable dress in the inner apartment, washes his hands and feet, steps through the door into the outer apartment, and resumes his ordinary clothing. The air of the interior of the stables should be kept saturated with moisture, in order to lessen the mobility of disease germs. When a stable is infected, all animals in it are to be removed, and kept under observation. Before removal they are to be well cleaned, and their hoofs washed in a disinfectant solution. The stables are then cleaned, and all floors, walls, and partitions scrubbed with water, after which they are to be sprayed with a solution of mercuric bichloride (1:500). After several hours' exposure to the action of the bichloride, the excess of this salt may be rendered innocu- ous by spraying all surfaces with a saturated sulphuretted hydrogen water, diluted with ten parts of water. A simple lime wash would probably answer equally well. Laplace has found that by adding an acid to a solution of mercuric bichloride or carbolic acid the germicide power of the latter is much increased. A two per cent, solution of carbolic acid, to which one half per cent, of hydrochloric acid has been added, will destroy the spores of anthrax, while without the addition of the hydrochloric acid the carbolic acid is inefficient for the destruction of these spores in five per cent, solu- tion. Tartaric acid acts in a similar manner when added to the disin- fectant.
Key Takeaways
- Test new disinfectors thoroughly before use
- Use multiple thermometers for accurate temperature monitoring during disinfection
- Mercuric bichloride is effective but can be hazardous; consider alternatives like carbolic acid
Practical Tips
- Regularly test and maintain your disinfection equipment to ensure it functions properly.
- Use a wire basket in the disinfecting chamber for better air circulation and disinfection of items.
- Consider using multiple thermometers to monitor temperature during the disinfection process.
Warnings & Risks
- Be cautious with pressurized systems; they can be dangerous if mishandled.
- Mercury-based disinfectants like mercuric bichloride can be harmful and should be used with caution.
- Ensure proper ventilation when using chemical disinfectants to avoid inhalation of fumes.
Modern Application
While the specific apparatuses described in this chapter are no longer in use, the principles of thorough testing, accurate temperature monitoring, and the importance of germ theory remain relevant. Modern survival preparedness can benefit from understanding these historical methods as a foundation for developing robust sanitation protocols.
Frequently Asked Questions
Q: What is the Henneberg disinfector used for?
The Henneberg disinfector uses steam to disinfect articles by heating them to high temperatures. It consists of two cylinders, one for containing the items and another as a boiler for generating steam.
Q: How does the Henneberg disinfector ensure that the steam is superheated?
The steam in the Henneberg disinfector is superheated by passing it over the heated surfaces of the sides of the boiler, which increases its temperature before it enters the disinfecting chamber.
Q: What are some common items that were disinfected at the Berlin public station?
Commonly disinfected items included clothing, body linen, feather beds, mattresses and bolsters, furniture, and other household goods. The station also handled rags, furniture trimmings, and articles from potentially infected places.
Q: What is the cost of using the Berlin public disinfecting station?
The cost for disinfection at the Berlin public station was four marks ($1.00) per cubic meter, including bringing and returning the items. For rags, the charge was one mark (24 cents) per 100 pounds.
Q: What is the recommended method of disinfecting apartments after an infectious disease outbreak?
The recommended method involves saturating the floor with a mercuric bichloride solution, spraying walls and ceilings until they are moistened, mopping the floor dry, washing it, and finally spraying the walls and ceiling again with a soda solution to form oxychloride of mercury.