Actual Conditions Of Use Research Articles

Guidelines for the comparative testing of detergent products

AbstractComparative testing of the performance of detergent products requires a flexible approach which takes full account of the actual conditions of use of these products by consumers. The AIS has developed guidelines for such a flexible approach, which after the normal international consultations, are now available as ISO standard No. 4319. The large differences in consumers’ practices between countries and the continuing changes in all countries do not allow development of international standard procedures for comparative testing of detergents, nor does it seem relevant to use test results from one country in another country. There is, of course, one consolation in all this complexity. If consumers occasionally pick a detergent less suitable for the purpose in mind, it will not cause damage, it will not cost much money, and let’s face it, consumers do like to do some comparative product testing themselves.

Microwave Mobile Monitonrng Techniques

Intelligent allocations and assignments lay the ground-work for electromagnetic compatibility; however, capability for measurements on emitters under actual-use conditions is necessary to ensure compliance with technical regulations, without which allocations and assignments mean little. Described in this paper is a vehicle-transported measurement system capable of measuring frequency, bandwidth, and other parameters of signals obtained "off-the-air" at the transmitting station site. Several alternative methods for these measurements are described, and suggestions for obtaining usable signals are provided.

Safety Evaluation Concepts

The approach to safety evaluation is strongly influenced by the standard of safety to which one aspires. Practical considerations demand that realistic limits be set to the attainable assurances of freedom from anticipated hazard under actual conditions of use of a product. The fact is that, in the interests of consumer health, more can be expected from a flexible, intelligent, and experienced approach to safety evaluation than from efforts at conformity with a set of rigidly standardized requirements that are theoretically all-encompassing. Establishment of safety demands a wide background of information about the properties and likely uses of the product; above all, knowledge of the chemical composition of the product and its impurities, degradation products, and metabolites is essential. Lack of such information is a frequent source of errors in safety evaluation. Based on a secure foundation of this sort, a program of investigations may be designed, aimed at establishing the basic biological properties of the material. Determination of the metabolic dynamics of the principal chemical agent or agents makes possible the emergence of a clear picture of the behavior of the compound(s) in the body and paves the way for more specialized studies of long term toxicity, carcinogenicity, effects on reproduction and teratogenesis, and investigations of multitest mutagenic potential. Emphasis is laid on the problems of interpretation of results in terms of hazard to man and on the crucial contribution that experience of human exposure can make toward assuring safety-in-use. Decisions on acceptable risk are the joint responsibility of many individuals but an essential element in reaching such decisions is contributed by the depth of understanding and broad experiences of the toxicologist.

A study — Early warning fire detection performance in the hospital patient room

These experiments, which represent fire situations in a hospital patient sleeping room, clearly indicate that a door frame-mounted detector provides one of the best locations for optimum detector response in this occupancy. Identification of air motion as the single most important factor influencing reaction time of early warning detection devices emphasizes the need to evaluate smoke and ionization detectors under actual conditions of use.

病院のエレベーター利用実態に関する調査

We obtained the basic date to estimate about one round trip time which is nesessary to estimate the standerd of elevater service in order to survey the actual conditions of use for hospital's elevater and the results are shown as follows, 1. the analysis of time zone on various activities in hospital 2. the patterns of user's getting on and off elevater 3. the avrage of the number of user and the rate of use for capacity on the elevater 4. the time required for user's getting on and off elevater.

Antimicrobial Activity of Dermatomucosal Agents

Dermatomucosal agents act in a local manner on the skin and mucous membranes and are, in general, not regarded as materials which alter the microbial flora of the body. The present study was undertaken to determine whether they are, in fact, microbiologically inert. Nine categories of dermatomucosal agents were established and at least six commonly available products were investigated in each category. Products were evaluated for antimicrobial activity by the “small tube method” and by filter disk zone of inhibition method utilizing 12 organisms representative of the normal aerobic skin flora as substrates. Results indicate a wide range of antimicrobial activity among dermatomucosals with the distinct possibility that such products may, in actual conditions of use, alter normal human skin flora leading either to beneficial or deleterious results.

Diffusion Couples as Electrical Insulation Aging Monitors

Most aging phenomena are temperature dependent as indicated by the Arrhenius equation. Knowledge of probable aging rates is necessary for practical engineering design of equipment, and aging rates of many electrical insulation systems have been studied in detail. Service life expectancies can therefore be confidently estimated for particular insulation systems in specific thermal environments. However, it is not possible to assure that all electrical equipments will be operated within the design environments and ratings. Thus, variations in service life performance of electrical equipments often reflect variations in operating conditions. It has not been economically feasible to measure actual conditions of use and exposure of most electrical equipments. An inexpensive monitor of thermal exposures has been recently developed. The resistance changes of bimetallic elements are in accord with the Arrhenius model for normal diffusion. Selection of metals that interdiffuse with temperature sensitivity equivalent to that of an insulation system of known thermal aging behavior allows use of the bimetallic diffusion couple as an indirect monitor of the actual insulation thermal degradation. A preferred form of the bimetal is a composite wire, comprising alternate concentric layers of two pure metals. The diffusion couple must be placed in a location which exhibits a representative, if not identical, thermal exposure of the insulation system to be monitored. The monitors may be built-in and read in-situ or they may be inserted as replaceable probes which can be retrieved and returned to a central test facility for evaluation.

An in vivo technique for determining the effect of agents on enamel solubility in human subjects

IT is desirable to perform enamel solubility studies in viva on human subjects, since this is the ultimate test of the efficacy of compounds in increasing the resistance of enamel to acid attack under actual conditions of use. WALTER (1958), and M~~HLEMANN and WOLGENSINGER (1959) have developed a method for such an in viva determination utilizing 2 mm disks of filter paper. Etching solution is placed on this small piece of paper and enamel solubility is determined by the length of time required to change an acid-base indicator on the disk or by a phosphorus determination (WALLIS, 1961). This procedure is restricted to small, smooth, intact areas. Moreover, it would probably be difficult to perform analyses on lingual surfaces of any tooth and buccal surfaces of posterior teeth. A procedure has been developed in our laboratories to determine enamel solubility conveniently on any upper tooth in vivo. Anterior or posterior teeth which were to be extracted for either prosthetic or periodontal reasons were selected for testing. The teeth used in preliminary studies were relatively free from caries, fillings, and other obvious defects. The subject was placed in position so that the long axis of the test tooth was always perpendicular to the floor in order to prevent loss of the etching solution. A small polyethylene vessel containing a measured amount (usually 2 ml) of 0.2 M acetate buffer, pH 4.0, was placed over the tooth. The top of the container was placed in contact with the gingiva. When this was not possible, the position of the vessel was marked on the tooth surface. This procedure enables the investigator to expose the same area to multiple etchings. Isolated teeth or adjacent teeth with diastemas are best suited for study using this technique. A typical experiment is performed as follows: The subject brushes his teeth with a placebo dentifrice and rinses his mouth thoroughly with water. The teeth being studied are etched with 0.2 M acetate buffer, pH 4.0, for 5 min. The teeth are rinsed again thoroughly and the experimental agent applied. After re-rinsing, the teeth are etched once more for

A practical approach to evaluation of the germicidal efficiency of a general purpose military disinfectant.

The bactericidal activity of a general purpose disinfectant consisting of 25% sodium-o-phenylphenolate and 75% sodium-4- and 6-chloro-2-phenylphenolate was evaluated by a simulated in-use, surface-square dilution method. Common floor (asphalt, rubber, and unglazed tiles) and wall (stainless steel tile, ceramic tile, and painted wood) surfaces of various porosities and compositions were selected to simulate actual-use conditions. The method used consisted of inoculating the surfaces of 1-in. square sections of floor and wall covering with a test organism, air-drying the inoculated surface, applying the disinfectant, allowing it to act for 10 min, and recovering the survivors by plating. Confirmatory results of the standard phenol coefficient and use-dilution tests indicated 700 ppm of the disinfectant to be a safe use concentration. The in-use surface-square dilution studies have shown that this is a more than adequate safe concentration for stainless steel, both glazed and unglazed ceramic tile, and nonwaxed surface of asphalt tile. However, concentrations ranging between 2,500 and 6,000 ppm for plastic-fortified rubber tile, 1,500 and 2,000 ppm for waxed asphalt tile, and 2,000 ppm for painted wood were required to achieve 99.9% reduction of either Salmonella choleraesuis or Salmonella schottmuelleri. These results indicate that a disinfectant concentration derived from the Association of Official Agricultural Chemists use-dilution test cannot always be relied upon to provide a dependable index to actual safe use-dilution when a disinfectant is supplied to certain wall or floor surfaces.

A Practical Approach to Evaluation of the Germicidal Efficiency of a General Purpose Military Disinfectant

The bactericidal activity of a general purpose disinfectant consisting of 25% sodium-o-phenylphenolate and 75% sodium-4- and 6-chloro-2-phenylphenolate was evaluated by a simulated in-use, surface-square dilution method. Common floor (asphalt, rubber, and unglazed tiles) and wall (stainless steel tile, ceramic tile, and painted wood) surfaces of various porosities and compositions were selected to simulate actual-use conditions. The method used consisted of inoculating the surfaces of 1-in. square sections of floor and wall covering with a test organism, air-drying the inoculated surface, applying the disinfectant, allowing it to act for 10 min, and recovering the survivors by plating. Confirmatory results of the standard phenol coefficient and use-dilution tests indicated 700 ppm of the disinfectant to be a safe use concentration. The in-use surface-square dilution studies have shown that this is a more than adequate safe concentration for stainless steel, both glazed and unglazed ceramic tile, and nonwaxed surface of asphalt tile. However, concentrations ranging between 2,500 and 6,000 ppm for plastic-fortified rubber tile, 1,500 and 2,000 ppm for waxed asphalt tile, and 2,000 ppm for painted wood were required to achieve 99.9% reduction of either Salmonella choleraesuis or Salmonella schottmuelleri. These results indicate that a disinfectant concentration derived from the Association of Official Agricultural Chemists use-dilution test cannot always be relied upon to provide a dependable index to actual safe use-dilution when a disinfectant is supplied to certain wall or floor surfaces.

Some Factors in the Assessment of Gastric Antisecretory Drugs by a Sampling Technique

Samples of gastric contents from patients with duodenal ulcer were more often highly acid when they drank 120 ml. of milk-cream mixture every hour than when they ate a bland diet. The volume of the drinks and the timing of the samples determined this apparent difference. Long-acting propantheline bromide reduced gastric acidity a little when the patients ate the diet and more when they took the drinks of milk-cream alone. It is concluded that the clinical usefulness of gastric antisecretory drugs can only be assessed under the actual conditions of use.

Two Special Sensitometers<!--<xref ref-type="fn" rid="fn110.5594_J05543">*</xref>-->

Design features of two sensitometers are presented. One of the sensitometers is used to make sensitometric tests on positive film under printing conditions. The other is designed to produce exposures under sound recording conditions. The results of tests with both of these sensitometers emphasize the importance of making sensitometric tests parallel conditions of film use, and show some of the errors that occur in judging speed and contrast from sensitometric data obtained under conditions not corresponding to the actual conditions of use.