Furniture

FURNITURE (from French meuble), household items used for lying, sitting, storing things, and the like. Depending on the purpose, location, and method of use, the material and construction of furniture can be very diverse, just as the sanitary and hygienic requirements for furniture vary depending on the same conditions. From the standpoint of sanitation and hygiene, furniture must satisfy the following requirements: 1) withstand ordinary disinfection methods and cleaning by wet means; 2) not hinder the cleaning and ventilation of the room; 3) not favor the accumulation of dust and the multiplication of parasites; 4) displace as little air as possible and not impede daylight through windows; 5) not present a danger of injury or other hazards by design (e.g., in terms of fire); 6) correspond in size and weight to the character of the room; 7) meet by design the biological needs of man: body dimensions, normal posture during work and rest, cleanliness of food preparation and storage, storage of tableware, clothing, linen, books, etc. These hygienic requirements, when applied to a particular place, can receive various concrete, sometimes directly opposite expressions. For example, from the point of view of the danger of injury in residential apartments, light furniture is preferable to heavy, whereas in places of mass gathering of the public, e.g., in theaters, at railway stations, heavy and especially immobile furniture is preferable to light; for storing books in private apartments, closed bookcases are better than open ones because they prevent the accumulation of dust on books, whereas, conversely, in large book depositories, open bookcases are preferable to closed ones because they facilitate the removal of dust by vacuum cleaners, etc. School and industrial furniture must satisfy special requirements (see below). The material for furniture is usually wood, preferably of hardwoods, with plywood veneer from fine grades of wood. In residential quarters from a sanitary and hygienic point of view, the following wishes can be presented for furniture. Beds should be individual, single, without curtains and canopies that impede the access of air to the sleeper. In malarial areas, on the contrary, it is necessary to abandon this hygienic requirement and recommend tulle curtains for protection against mosquitoes. Children's beds should be equipped with lowering barriers consisting of a mesh stretched over a metal rod. The material for the bed is best nickel-plated, enamel-coated, or painted iron. Wooden beds are worse from the standpoint of ease of cleaning and especially disinsection. The bed should be soft enough. The best are beds with a mesh on which a light hair mattress is placed, or beds with a firm frame on which a spring mattress is placed. Furniture for sitting is best made of bent ("Vienna") polished wood. It is convenient for cleaning, light, displaces little air, and by design corresponds to the natural posture when sitting. From the point of view of cleanliness, polished furniture is best, because dust does not linger on a polished surface and catches the eye sharply. Painted furniture is worse, since the paint is easily damaged, resulting in cracks and recesses where dust and dirt accumulate. Unpainted, white furniture is cleaned of dirt more difficultly than painted furniture and, moreover, gives more cases of injury (splinters). Among upholstered furniture, leather is preferable. Among fabrics for furniture upholstery, from a hygienic point of view, smooth fabrics should be preferred to napped ones. Plush upholstered furniture is unhygienic in that it does not lend itself to cleaning and disinfection. Heavy, difficult-to-move sofas are also bad in that they displace a lot of air and promote the accumulation of dust under them. Tables for eating are preferably round, for writing—rectangular polished (Swedish-American). Cabinets should not be too heavy so that they can be moved during cleaning. In new construction, tightly closing niches (closets) should be arranged in the walls for storing clothing, linen, tableware, etc., which present great advantages both in a purely hygienic respect and because they facilitate cleaning and ventilation of the room, and most importantly, do not take up space in the room, which is especially important. In general, the task of area economy is a particularly important moment determining the design of new types of furniture (bed-sofa, table-cabinet, etc.). Carving on furniture is unhygienic because it extremely complicates cleaning, and from an aesthetic point of view, carving is good only when it is carefully cleaned of dust; otherwise, carved furniture will produce a rather anti-aesthetic impression. Carpets on the floor or walls, heavy curtains, draperies, and blinds are unhygienic because they promote the accumulation of dust and make cleaning difficult. If, for aesthetic reasons or for protection from the sun in hot weather, curtains and blinds are necessary, one should choose white washable fabrics and a light-weight, easily removable design. In general, direct sunlight is a powerful disinfectant, in some cases completely irreplaceable (tuberculosis), and it is necessary to block its access to the room only by virtue of actual necessity, when, for example, it interferes with work or sleep. Where possible, one should strive to replace flammable material with non-flammable material—metal, glass (cabinet walls, table tops). This is especially important in kitchens when using kerosene for cooking. Modern technology of mass factory production of furniture presents great opportunities for the use of new materials not used in artisanal furniture production (such as bent steel), new methods of polishing and painting, and new designs consistent with hygiene requirements and based on anthropometric measurements. Work on creating new furniture standards is particularly widely deployed in America, where special institutes exist for this purpose. In our country, new furniture standards are being developed by the All-Union Central Institute for Labor Health and Organization and other scientific institutes. In general, it must be said that modern household equipment, created according to the social order of the bourgeoisie, is poorly suited for the new forms of socialist life. The construction of socialist cities requires the development of new types of furniture that fully meet the needs of working people in new forms of their life and labor. This task is an urgent one for the immediate future.

El. Lissitzky, V. Rozanov. Industrial furniture is an extremely important type of furniture that serves workers throughout their entire work at enterprises. Its importance is determined by its impact on 1) labor productivity, 2) fatigue, and 3) the health of workers. However, experimental science has so far paid little attention to this issue, which is why the development of types of industrial furniture has been based exclusively on empirical data. In the USSR, for the first time in the All-Union Central Institute for Occupational Health and Organization of Labor (Moscow), a scientific and methodologically sound approach is being created to the study of the design of industrial furniture and to its physiological and hygienic evaluation. The main requirements for the rational design of industrial furniture consist in combining in the best possible way into a harmonious dynamic whole the living, working human body and the production environment surrounding it. Therefore, requirements of this kind can be subdivided into 1) biomechanical, 2) technical, 3) physiological, 4) hygienic, 5) economic, and 6) aesthetic. - Biomechanical requirements for the design stem from 3 main biomechanical forms of activity of the human body. a) In relation to the statics of the human body, the furniture design should serve primarily as a good support, maximally relieving static muscle tensions, and in addition, by its shape, promote an equal distribution of efforts in the human organism, ensuring a correct, least tiring posture. This requirement applies to the design of various fixed chairs, footrests, armrests, tables, etc. b) In relation to the kinematics of the human body, it is necessary to coordinate the movement of parts of the furniture (movable armrest, footrest, chair, etc.) with the natural movements of body parts, so that the former repeat or in any case do not constrain the latter. Often, complete disregard for the rules of biomechanics by the designer leads to the fact that the furniture design forces a person to make complex and unnatural movements. c) In relation to the dynamics of the human body, the furniture design should not only exclude "extra movements" but also ensure the possibility of such a physiological motor complex in which the achievement of the goal would be accomplished with the least expenditure of energy for the worker. Technical requirements for the furniture design: a) The design should rely on the standardization and unification of furniture types in order to achieve greater distribution and lower cost of rational furniture. b) The principle of interchangeability of furniture parts should be applied. c) The design should be technically as simple as possible (a small number of parts) with a reliance on simple and cheap methods of manufacturing furniture. d) All parts should be designed for standard grades of materials. e) The strength of the structure must be ensured (especially for dangerous professions), calculated for maximum dynamic efforts. Physiological requirements consist in the fact that the furniture design must ensure as far as possible normal states of the physiological functions of the human body (gas exchange, blood pressure, angle of vision, etc.) and thereby protect the body from fatigue and disease. - Hygienic requirements: a) Parts of the furniture in constant contact with the body must be made of a poor conductor of heat (e.g., wood). b) Good skin ventilation must be ensured if the human body is in contact with the furniture for a long time (all 8 hours). c) The edges and surfaces of the furniture must be smooth, even, rounded, and easily cleaned of dust, etc. - Economic requirements: a) Rational industrial furniture should contribute to an increase in labor productivity. b) Parallel to the increase in the quantity of manufactured rational furniture, a decrease in its cost is required. - Aesthetic requirements are determined by the fact that the design must be convenient, not bulky, and pleasing in appearance in form and color. Experimental methods of studying industrial furniture must provide 1) a base for the correct design of furniture, 2) an evaluation of existing structures. The first group of methods is essentially at the very beginning of its development and so far comes down to 2 types of biomechanical methods. Of these, special importance in this case is held by 1) the method of "rotational filming" (Bernstein), which boils down to photographing the studied posture for 4-5 seconds from 8 different points of view, which makes it possible with high accuracy to compile the so-called posture diagram, i.e., its complete geometric and mechanical plan; 2) the method of zenithal filming of posture (Saltsgeber); filming is carried out by a simple camera fixed strictly plumb, lens down, at a height of 2-4 m above the head of an industrial worker who is at his workplace and dressed in tight-fitting tricot, with white spherical buttons attached to each joint and identification points of the furniture and the workplace. Obtaining a single horizontal projection is sufficient only for studying the projection of the position of the centers of gravity of the links onto a horizontal plane and for calculating the distribution of the resultant static muscle tensions and static moments. To establish the dimensions of body parts and their mutual arrangement, photo-registration from the side (optical axis strictly horizontal), performed simultaneously with the zenithal one, is added to the specified type of filming. The obtained images are measured at 1/5-1/10 of natural size under a projection lamp either by hand or using photopromer, and the true values of dimensions, distances, differences, static moments, and muscle tensions are obtained by simple calculation according to the rules of ordinary projective geometry and theoretical mechanics. Thus, using these methods, the biomechanist physician provides the engineer with a) exact dimensions, b) distances, c) differences, d) data on the distribution of the centers of gravity of the links (necessary for taking into account the location of the centers of the support surfaces), and e) the values of the resultant muscle efforts in the links of the body. As for the shape of the support surfaces - no less important a department of the design - it can be obtained in the form of plaster casts of those parts of the body for which they are intended. Thus, for example, the type of chair developed by the All-Union Central Institute for Occupational Health and Organization of Labor has a seat built according to the average data of casts of average people (men and women). To the second group of methods, which evaluate an already finished design, belong the following: 1) Biophysical methods for registering the efficiency of support surfaces,

Figure 1.

e.g., to assess the role of the lumbar backrest, it is convenient to use a specially constructed (by designer Pavlenko) dynamometer (Fig. 1), which allows measuring the pressure on the backrest at a certain posture, and subject to the attachment of a kymograph to it, also graphically recording changes in pressure on the backrest during work. This device can also be easily used in any production environment if you place it against the worker's lower back during work. Another device - the polymanometer (Fig. 2), also constructed at the All-Union Central Institute for Occupational Health and Organization of Labor (Saltsgeber) on a different principle - allows quantitative accounting of the distribution of the pressure of the sitting person's body on various support surfaces. For this purpose, for example, the tested seat is provided with several dozen holes into which glass tubes filled with liquid are inserted, and it is attached to a small table with a stand for manometric tubes. Each manometric tube is connected to the tube in the seat by a rubber hose, and the open ends of the tubes in the seat are covered with thin rubber (like a Marey capsule). - 2) Of the physiological methods used as indirect methods assessing the effectiveness of furniture, one can mention the study of gas exchange. However, it must be borne in mind that it provides data only on the degree of severity of the posture for a person with different furniture, but does not provide direct indications of its connection with the reaction of the support surface. Generally speaking, all methods serving to characterize the degree of fatigue, including psychotechnical ones, can also be used here. 3) An important factor for evaluation can be the method of accounting for productivity. 4) No less important is the questionnaire survey of the workers themselves. Of course, comparative experiments must be carried out on people equally well accustomed to rational and irrational furniture. The most important emerging types of rational designs of industrial furniture are the following: I. Industrial furniture providing a rational support surface. - 1) Universal chair (made of iron and wood, Fig. 3), constructed at the All-Union Central Institute for Occupational Health and Organization of Labor. The features that favorably distinguish it from chairs of other designs are the following: a) Extremely simple movement of the seat in height with a light push of the foot on the pedal, b) Correct saddle-shaped form of the seat, having an anteroposterior slope, c) Variability of the rotational ability of the seat, such as: for hazardous work - complete locking; when working with an auxiliary zone - rotation by 120° and finally complete rotation, d) The possibility of attaching various armrests and footrests, e) Interchangeability

Figure 2. rigidity of various parts of the chair, e) Variability of backrest movements (not only vertically, but also horizontally). Figure 4 clearly proves the necessity of such backrest displacements in connection with the displacements of the center of gravity of the upper half of the body at different postures and different lengths of the torso.- 2) The universal chair of the VCIUOT type, simplified and cheapened (wood), basically has the same properties as the first chair. This design is extremely convenient in that, despite its universality, it completely lacks metal parts, which is important given the presence in our country of a large raw material base of forest materials. Instead of steel springs, a bent, springing birch board is used. The cost of this chair is also significantly lower.-3) The seat of the chair (Fig. 5) represents an even greater simplification due to the fact that it cannot be changed in height. These chairs are ordered by numbers. The height of different numbers differs by 3 cm from each other.-4) The principles of designing universal chairs also give instructions for various palliative

Figure 3.

FIG. 4.

measures in the field of rationalizing old furniture. Figure 6 gives an illustration of rationalizing a simple stool, to which a backrest and an armrest are attached.-5) To service long workstations, movable work chairs of two types are planned (Fig. 7 and 7a): a) movable on foot casters, b) movable on rollers at the seat itself.--6) For professions that work either sitting or standing, folding chairs are made (Fig. 8).-7) For work at inclined workstations, corresponding inclined chairs are created.-8) In Germany, where after the war and during it the labor of the disabled was widely used,

Figure 5.

Figure 6.

Figure 7.

special suspended armrests for stumps attached to the machine were used (Fig. 9).- 9) For moving, tense hands of such professions as female dispatchers-motorists, punch card operators, etc., movable armrests are recommended, mounted on a well-stretching spring and repeating natural movements.- 10) Workers who, by the nature of their profession, cannot work sitting down, are given the opportunity to rest during work breaks on special folding chairs that do not take up space in the aisle (collapsing).-11) For some standing jobs, special supports (project by N. Haeberle) are also made to unload the back muscles when standing (Fig. 10).-12) For work where there are large movements of one leg, as well as for the disabled, chairs with cutouts in the seat for this leg are suitable.-13) In working conditions when there is floor vibration, it is advisable to use springing pads (rubber) under the legs of the chair, as indicated in Fig. 11 (Gilbreth's project), and also to use a spring.-14) For recreation rooms located next to the workshop, folding seats made of wood and canvas are convenient and cheap, changing the degree of their inclination at will. Other types of rational industrial furniture: 1) It is possible to note the rationalization of furniture produced by the pharmacy administration mainly in Moscow pharmacies, generally quite successful, if we do not count the too low location of the lower drawers and shelves in the cabinets. 2) The project of a sorting table for sorting letters (Rudnik) deserves attention. 3) The VCIUOT is working on the issue of revising the design of the upper surface of the work table. The expediency for some professions of arranging a small inclination of the table surface, which makes it possible to sit more straight at the table and work with a normal viewing angle, is becoming increasingly clear. 4.) It is also necessary to mention furniture for cloakrooms: a) rational clothes lockers (Germany) and b) shoe-shining stool-boxes installed in the cloakrooms of dusty and dirty workshops. It must be noted that the first steps in introducing rational furniture into industry in our country have already yielded results. At present, 3 works have been completed, proving the economic efficiency of rational chairs designed by VCIUOT. A large number of positive reviews from workers and production workers about the first samples of working furniture, which was tested by the Institute at a number of factories and plants, have been collected. The drawings of work tables and chairs with

all reviews have been transferred to the All-Union Committee on Standardization for standardization on an all-union scale.-The success of introducing the rationalization of industrial furniture requires, of course, great cultural and educational work and special training of workers in the correct use of the proposed design.

O. Zandgeber. Furniture for children's institutions must also be constructed on the basis of physiological requirements for the correct posture of the body during work, and the functions of breathing, blood circulation, the organ of vision and the musculoskeletal system must not be disrupted. Correct posture

Figure 8.

of the body during work is achieved by the active work of muscle groups supporting the trunk in a position of stable equilibrium. Fatigue of muscle groups occurring under unfavorable working conditions, e.g. with its excessive duration, lack of sufficient lighting, with irrationally arranged furniture, leads to a weakening of muscle tone and a shift in the centers of gravity of the body

and its individual segments, the consequence of which are incorrect postures harmful to health. As a result of prolonged incorrect body position, persistent changes in the body develop—stoop, scoliosis, weakened vision, etc.; the general resistance of the body decreases, anemia develops, etc.-Of particular importance for children who are in the process of growth and development are the preservation of the correct body position and the development of appropriate skills associated with the use of furniture. The weakening of muscular efforts is largely facilitated by external points of support provided in correctly arranged working furniture; thus, a correctly arranged backrest provides support in the lumbar and lower thoracic spine, the correct height of the chair contributes to the support of the foot on the floor or a stand, etc. The requirements presented here for correct furniture consist in the fact that the dimensions and relationships of the table part and the seat must correspond to the proportions of the child's body. Body lengths determining the main dimensions of furniture are in direct correlative connection with growth, and therefore growth serves as an indicator when determining the dimensions of furniture for different age groups of the population. When determining

Figure 10.

Figure 11.

experiment and anthropometry. The method of observations and measurements was first applied in America by Bernard (1838) to determine the dimensions of children's furniture. Then a number of authors developed tables of school furniture dimensions, which were adopted by legislation in various countries. In Russia, the first table of furniture dimensions for schoolchildren was developed by Erisman based on data from measurements and long-term observations of students in St. Petersburg gymnasiums (1871–1905). In 1927/28, at the State Institute of Social Hygiene in Moscow, this issue was re-examined using a special methodology of anthropometric measurements of children who assumed a correct body posture on a special measuring chair by Stefani, followed by variational-statistical processing of the materials. Similar work, using a somewhat modified methodology, was carried out in 1931 by the Institute for the Protection of Motherhood and Infancy of the People's Commissariat of Health on toddlers of nursery age. As a result of a mass survey of children from nurseries, kindergartens, and schools in Moscow, a table of furniture dimensions for children and adolescents from 1 year to 19 years of age was developed (Table 1). Data from anthropometric measurements of children show large variations in individual body sizes by which the main dimensions of furniture are determined, and therefore precisely fitted furniture must be individual or change in its main dimensions, mainly in the height of the table, seat, and backrest. Correct posture depends mainly on the correctly established dimensions of the differential, i.e., the distance from the edge of the table facing the sitter to the edge of the seat; on the backrest distance, i.e., the distance Table 1. Main dimensions of furniture for children and adolescents (in cm). Chair dimensions Differential Table dimensions [Table data omitted in OCR or unrecoverable]

Figure 12. Schematic cross-section of the table: A—seat height; B—bench width or chair depth; C—height of the lumbar backrest; D—additional value for the spino-lumbar backrest; E—differential; F—seat distance; G—backrest distance; H—width of the inclined part of the board; I—width of the horizontal part of the table board; J—rise of the table top; K—height of the edge of the table facing the sitter.

at least from two sides. Single and double desks are portable and can be used for various groupings during work; the same desks can be adapted for different types of work. Desks with an inclined board, which best meet the requirements of visual hygiene during reading and writing, can be converted into desks with a horizontal board, more convenient for other work. Individual folding desks are especially desirable in view of the possibility of using them for outdoor work. In order to save space and facilitate quick and easy cleaning of the room, folding tables are also used, e.g., for eating. Special workbenches must be adapted for children of different heights and meet all the requirements of the labor process under conditions of working sitting and standing. Tables in school laboratories—chemical, physical, and biological—differ in shape and the arrangement of special drawers for storing materials and supplies; they require connections for electricity, gas, water, etc. The most rational seating from a hygienic point of view is chairs or benches with lumbar and spino-

Figure 13. Correct and incorrect postures at school desks (left to right): at a low desk and with a positive seat distance; at a low desk and a low bench; at a high desk and at a desk of appropriate dimensions.

lumbar backrests; backrests in the form of separate horizontal or curved bars are quite satisfactory. Such backrests, the height of which is determined based on data on the height of the lumbar curve and the height of the lower angle of the shoulder blades above the seat, fully provide support for the spine. A necessary condition for the correct design of these backrests is the absence of longitudinal crossbars between the bars that interfere with correct sitting. Solid backrests must conform to the curves of the spine. For laboratories, the chair developed by the All-Union Central Institute of Labor (see above) is most acceptable. An indispensable condition for the correct supply of children's institutions with working furniture is the correct selection of tables and chairs according to the sizes of the corresponding furniture numbers and

Table length—100 cm

Figure 14. Types of school desks: 1—Erisman desk; 2—Schütte desk; 3—Ivanovsky desk; 4—universal desk.

its correct distribution among children's groups. For this purpose, tables and chairs with stamps of certain numbers should be put on sale. The percentage distribution of children from different children's institutions by height should serve as a guideline when ordering furniture for them (Fig. 14). Auxiliary furniture in children's institutions includes cabinets for various purposes—for books and supplies, for individual and collective work, specially exhibition cabinets, cabinets for clothes, etc. Cabinets should not displace much air and contribute to the accumulation of debris and dust. In height, the cabinets should correspond to the height of the children and have a small width for the convenience of reaching things and easy cleaning. Cabinets should either stand on legs 15–20 cm high or be portable, easily movable, on a solid frame tightly adjoining the floor. Individual enclosed clothes cabinets with shelves for headwear must have ventilation devices. In the absence of such, cabinets with an open front wall are preferred. In order to unload the room, it is advisable to arrange wall cabinets in both working and utility rooms of children's institutions. In addition, special drying cabinets (for linen and clothes) with warm air supply are arranged in children's institutions. Children's furniture in the home environment of the child must meet the same hygienic requirements. The development of sanitary and hygienic requirements and standards of furniture for children and adolescents is carried out in the institutes of protection of motherhood and infancy and the protection of health of children and adolescents of the People's Commissariat of Health, and the development of samples of Polytechnic equipment—in the Institute of Polytechnic Education of the People's Commissariat of Education. At the Institute of Social Hygiene (1929), the question of the dimensions of the table and chair for mental workers was developed on the basis of special measurements of students of the Higher Technical School in Moscow (Table 2). Table 2. Table of average dimensions of furniture for mental workers (in cm). For groups with height Furniture I from 155 to from 165 to III cm

174 cm I 1 Table dimensions Width (anterior-posterior dimension) . . Length of the workplace at the general table . . . Length of the individual table . . . . . Chair dimensions Seat height . . . Depth (anterior-posterior dimension) . . 38 Height of the upper edge of the backrest above FROM 175 TO 185 cm 120 30 47.5 38 40 81 60 120 31 40 43 The percentage distribution of furniture according to the height groups indicated in the table gave 16% for number 1, 62% for number 2, and 22% for number 3. The furniture available on the market in the USSR is designed according to average "standard" sizes and thus can be correctly applied to approximately only 62% of the male population. Taking into account that the height of women is on average lower than that of men, the correct use of this furniture is even less. In mass production and supply of public institutions with furniture of fixed dimensions, the height distribution must be taken into account. The problem of furniture has only just been posed here; for its correct resolution, it is necessary to elaborate types, sizes, and designs and establish grades and qualities of building materials meeting the hygienic requirements of a cultural dwelling, and to organize standard production of basic furniture items. The problem of furniture must be developed in connection with the reorganization of labor and living conditions and in close contact with the new socialist housing construction. Hospital furniture—see Hospital, hospital equipment.

M. Koreunskaya.