C/3. 1.0/ Z. : 63- 7£- Voluntary Product Standard PS 63-75 U.S. DEPARTMENT OF COMMERCE/ National Bureau of Standards LATEX FOAM MATTRESSES FOR HOSPITALS American National Standards Institute American National Standard Z 255.1-1975 o a 9 a A D NATIONAL BUREAU OF STANDARDS The National Bureau of Standards 1 was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, ( 3 ) a technical basis for equity in trade, and (4) technical services to promote public safety. 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UNITED STATES DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS • Richard W. Roberts, Director Voluntary Product Standard PS 63-75, Latex Foam Mattresses for Hospitals Approved by the American National Standards Institute on February 3, 1975, as American National Standard Z255. 1-1975 Abstract The purpose of this Voluntary Product Standard is to establish nationally recognized dimensional and quality re- quirements for latex foam mattresses intended for use in hospitals, and to provide producers, distributors, and users with a basis for common understanding of the characteristics of this product. Key words : Foam mattresses ; hospital mattresses ; latex ; latex foam mattresses ; latex foam for hospitals ; mat- tresses. Nat. Bur. Stand. (S.U.), Prod. Stand. 63-75, 8 pages (April 1975) CODEN : XNPSAX For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (Order by SD Catalog No. C13.20/2 :63-75). Price 50 cents Digitized by the Internet Archive in 2012 with funding from LYRASIS Members and Sloan Foundation http://www.archive.org/details/latexfoammattresOOunit Contents 1. Purpose * 2. Scope . 1 3. Kequirements 1 3.1. General 1 3.2. Flammability 1 3.3. Mattress cover 1 3.3.1. Material 1 3.3.2. Construction 2 3.3.3. Dimensions 2 3.3.4. Stitching 3 3.3.4.1. Thread 3 3.3.4.2. Seams and stitching 3 3.3.4.3. Sewing (anchoring) tape 3 3.4. Mattress insert 4 3.4.1. Material 4 3.4.2. Dimensions . 4 3.4.3. Construction 4 3.4.3.1. Surface defects 4 3.4.3.2. Insert reinforcements 4 4. Inspection and Test Procedures 4 4.1. Resistance of the cover to mineral oil 4 4.2. Exceptions to Method 6711 when testing for resistance of the cover to alcohol 4 4.3. Exceptions to Method 6711 when testing for resistance of the cover to phenol 4 4.4. Exceptions to Method 7411 when testing for resistance of the cover to steriliza- 4 tion 4 4.5. Exceptions to ASTM D 1203-67 (Method A), when testing plasticizer loss of the cover 4 5. Identification . 6. Effective Date 5 7. History of Project 5 8. Standing Committee 5 Appendix A — Care of Latex Foam Mattresses 5 Appendix B — Metric Conversion 6 ill VOLUNTARY PRODUCT STANDARDS Voluntary Product Standards are developed under procedures published by the Department of Commerce in Part 10, Title 15, of the Code of Federal Kegulations. The purpose of the standards is to establish nationally recognized requirements for products, and to provide all concerned interests with a basis for common understanding of the characteristics of the prod- ucts. The National Bureau of Standards administers the Voluntary Product Standards pro- gram as a supplement to the activities of the private sector standardizing organizations. Establishment of a VOLUNTARY PRODUCT STANDARD The role of the National Bureau of Standards in the establishment of a Voluntary Product Standard is to (1) act as an unbiased coordinator in the developmentof the standard, (2) pro- vied editorial assistance in the preparation of the standard, (3) supply such assistance and review as is required to assure the technical soundness of the standard, (4) seek satisfactory adjustment of valid points of disagreement, (5) determine the compliance with the criteria of the Department's procedures, (6) provide secretarial functions for each committee appointed under the Department's procedures, and (7) publish the standard as a public document. Producers, distributors, users, consumers, and other interested groups contribute to the establishment of a Voluntary Product Standard by (1) initiating and participating in the development of the standard, (2) providing technical or other related counsel as appropriate relating to the standard, (3) promoting the use of and support for the standard, and (4) assisting in keeping the standard current with respect to advancing technology and market- ing practices. Use of a VOLUNTARY PRODUCT STANDARD The use of a Voluntary Product Standard is voluntary; the National Bureau of Standards has no regulatory power in the enforcement of the provisions of the standards. However, since the standards represent a consensus of all interested groups, their provisions are likely to become established as trade customs. In addition, when a standard is made a part of a legal document, such as a sales contract or code, compliance with the standard is enforceable. The benefits derived from Voluntary Product Standards are in direct proportion to their gen- eral recognition and actual use. Producers and distributors whose products meet the require- ments of a Voluntary Product Standard may refer to the standard in advertising and on labels to promote greater public understanding of or confidence in their products. Purchasers may order products conforming to the requirements of the standards. For copies of the Voluntary Product Standards procedures or for more information concern- ing the development and use of these standards you may write to : Standards Development Services Section, National Bureau of Standards, Washington, D.C. 20234. Voluntary Product Standard PS 63-75 Latex Foam Mattresses for Hospitals Effective February 3, 1975 (See section 6.) (This Standard, initiated by the Rubber Manufacturers Association, has been developed under the Procedures for the Development of Voluntary Product Standards, published by the U.S. Department of Commerce, as a revision of Commercial Standard CS 182-51, Latex Foam Mattresses for Hospitals.) 1. PURPOSE The purpose of this Voluntary Product Stand- ard is to establish nationally recognized dimen- sional and quality requirements for latex foam mattresses intended for use in hospitals, and to provide producers, distributors, and users with a basis for common understanding of the char- acteristics of this product. 2. SCOPE This Voluntary Product Standard covers re- quirements and methods of test for the materials, dimensions, and construction of latex foam mat- tresses intended for use in hospitals. Methods for identifying products that conform to this Stand- ard are provided. Information regarding the care of latex foam mattresses is given in Appendix A. Note: As an aid in correlating U.S. customary units to metric units conversion factors for units used in this Standard are given in Appendix B. 3. REQUIREMENTS 3.1. General— All latex foam mattresses repre- sented as complying with this Voluntary Product Standard shall meet all of the requirements speci- fied herein. Later issues of publications refer- enced in this Standard may be used providing the requirements are applicable and consistent with the issue designated. Copies of standard FF4-72, Standard for the Flammabllity of Mat- tresses} or its successor, are available from the Consumer Product Safety Commission, Washing- ton, DC 20207. Copies of Federal (FED) Stand- ards and Specifications are obtained from Spe- cification Sales (3FRDS), Building 197, Wash- ington Navy Yard, General Services Administra- tion, Washington, D.C. 20407. American Society for Testing and Materials (ASTM) publications are available from ASTM offices, 1916 Race Street, Philadelphia, Pa. 19103. 3.2. Flammability — Mattresses shall comply with the flammability requirements of FF4-72, which has been issued as a mandatory standard under authority of the Flammable Fabrics Act as amended in 1967. 3.3. Mattress cover 3.3.1. Material — The mattress cover shall be made of cloth coated with plastic at least on the exposed surface and shall have the properties shown in table 1 when tested as specified therein. 'All mattresses, including hospital mattresses, must meet FF4-72, amended June 8, 1973. It is recognized that additional flammability requirements such as those given in MIL-M-18351E, Mattresses, Berth, Synthetic Sponge Rubber, Naval Shipboard (available from Naval Publica- tions and Forms Center, 580 Tabor Avenue, Philadelphia, Pa. 19120), may be desired and specified under certain conditions by some purchasers. Table 1. Properties and test methods for the mattress cover Property Requirement Test Method Exceptions to referenced test methods Breaking strength 115 lb in warp direction (min) 90 lb in fill direction (min) ASTM D 751-73, Standard Methods of Testing Coated Fabrics, Sections 8 through 12 Speed of pulling clamp shall be 12 + y 2 inch/min Resistance to blocking Blocking not more than slight FED 191, Method 5872 Adhesion of 4 lb per inch of width (min) ASTM D 751-73, coating Sections 39-42 Thickness of 0.004 inch on the exposed FED 601, Method 2011 The thickness determina- coating surface (min) tions shall be made by Hydrostatic resistance Resistance to alcohol Resistance to phenol Resistance to sterilization Plasticizer loss Resistance to mineral oil No evidence of leaks at 15 lb/in 2 No evidence of softening, tackiness, hardness, peeling, cracking, or other damage affecting serviceability. Same as above requirement. Same as above requirement. 8 percent (max) No penetration ASTM D 751-73, Sections 30-34 FED 601, Method 6711 FED 601, Method 6711 FED 601, Method 7411 ASTM D 1203-67, Standard Methods of Test for Loss of Plasticizer from Plastics (Activated Carbon Method), Method A See 4.1 of this standard comparing the cover thickness of identical spots before and after stripping the coating. Flex each specimen five times within one minute by applying and releas- ing a pressure of 15 psi. After the fifth flex, maintain the pressure at 15 ± 1 psi for five minutes. See 4.2 of this standard. See 4.3 of this standard. See 4.4 of this standard. See 4.5 of this standard. 3.3.2. Construction —The mattress cover shall be constructed of top, bottom, and side panels. The mattress cover can either be removable or nonremovable as agreed upon between buyer and seller. If the cover is removable, it shall be de- signed so that it can be opened and closed using a fastener to allow for the removal of the insert. The top panel and bottom panel shall each be one continuous piece, and the side panel shall be either one continuous piece or two pieces. If the side panel is made from two pieces, the fastener shall be completely mounted in one of these pieces. The fastener shall be positioned in approximately the center of the vertical dimension of the side panel and shall open over at least one end plus one-half of the length of the mattress. The fast- ener shall meet the requirements for type 1, style 8, size LM, short tab pull, of FED-V-F-106d, Fastener, Slide Interlocking. The cover may or may not have lifting straps as agreed upon between buyer and seller. If the cover has lifting straps, there shall be two lifting straps on one side (or both sides) approximately 36 inches apart and equidistant from the ends of the mattress. The straps shall be made of the same material as the cover ; they shall be securely attached in a vertical position to the top and bot- tom of the finished mattress border at the seams. 3.3.3. Dimensions — The nominal length and width of the top, bottom, and side panels of the mattress cover shall be as agreed upon between buyer and seller. The tolerances on the nomi- nal length and width of the top and bottom panels shall be plus or minus 0.5 inch on the length of the side panel and plus or minus 0.2 inch on the width of the side panel. The corners of the top and bottom panels shall be square, or round with a radius not exceeding 3 inches. The dimensions, except for the length of the side panel, shall be measured from seam to seam by using a yardstick, metal tape, or any suitable measuring device. The part of the cover to be measured shall be laid smooth, without tension, on a horizontal surface. Length shall be measured parallel to the length- wise direction, and width shall be measured in a line perpendicular to the lengthwise direction. The length of the side panel shall be the perimeter of the cover measured at the centerline whether the panel is constructed of a continuous piece or two pieces of fabric. In all cases other than the length of the side panel, the dimensions shall be the average of at least five different measure- ments uniformly distributed throughout the seg- ment being measured. 3.3.4.2. Seams and stitching— References to seams and stitching pertain to FED 751, Stitches, Seams, and Stitching. All stitching shall have a %-inch minimum seam allowance and 10 to 12 stitches per inch. The ends of all seams not caught in other seams or stitching shall be securely back- stitched from % to 1 inch. Skipped stitches or thread breaks shall be repaired using the same type of stitch or same combination of stitches as the basic stitching. The fastener shall be sewn to the side panel using stitch type 301, seam type SSs-2. If the side panel contains two pieces they shall be joined together using stitch type 301, seam type SSa-1. The side panel shall be sewn to the top and bottom panels using a combination of stitch type 301 and either type 503 or 504, seam type SSa-2. 3.3.4. Stitching 3.3.4.1. Thread — All thread shall have a mini- mum breaking strength of 3.0 pounds when tested in accordance with ASTM D 2256-69, Standard Method of Test for Breaking Load (Strength) and Elongation of Yarn by Single-Strand Method. Option 1A, which refers to straight, conditioned specimens, shall be used. 3.3.4.3. Sewing (anchoring) tape— In the case of a nonremovable cover, a sewing tape shall be adhered to the outer periphery of the latex foam insert, and the free (nonadhesive) portion of the sewing tape shall be sewn into the mattress bind- ing tape when the top and side panels of the cover are sewn together; this will prevent the insert from slipping around inside the nonremovable cover. Table 2. Properties and test methods for the mattress inserts Property Compression set 25 percent indentation load deflection (ILD value) Requirement Test method 10 percent (max) loss of original height 30 ± 6.0 pounds for thick- nesses up to and including 4 inches. 40 ± 7.0 pounds for thicknesses over 4 inches. ASTM D 1055-69, Standard Specifications for Latex Foam Rubbers, sections 17 through 19 ASTM D 1055-69, sections 20 through 23 Exceptions to referenced test methods The time of exposure shall be 22 ± 0.2 hours. Two specimens shall be tested, one at the center of the insert, and one between 4 and 20 inches from either end of the insert on its center line. The specimen shall be compressed at any rate between 10 and 25 inches per minutes (between 4 and 10 mm/sec) Change in 25 percent ILD value after aging Flexing endurance 20 percent (max) 5 percent (max) loss of original height, and 30 percent (max) decrease in 25 percent ILD value ASTM D 1055-69, sections 15 and 16 ASTM D 1055-69, sections 24 through 26 Specimen to be aged in accordance with ASTM D 573-67, Standard Method of Test for Accelerated Aging of Vulcanized Rubber by the Oven Method, for 22 ± 0.2 hours at tem- perature of 212 ± 3.6 °I (100 ± 2 °C) 3.4. Mattress insert 3.4.1. Material— The mattress insert shall be made from rubber latex foam having intercon- necting cells and shall have the properties shown in table 2 when tested as specified therein. 3.4.2. Dimensions — The dimensions of the in- sert shall be from 0.1 to 3.0 percent greater than the dimensions of the cover when tested in ac- cordance with section 14 of the ASTM D 1055-69, Standard Specifications for Latex Foam Rubbers. 3.4.3. Construction— The insert shall consist of not more than three sections, except that a maxi- mum of iy 2 inches of the same material as the insert may be added to the length and to the width to adjust for size. All pieces of the insert shall be cemented together so that the joints cannot be felt through the mattress cover and so that they can- not be separated by hand except by tearing the latex foam. Core holes shall be not greater than iy 2 inches in diameter, and in addition, if a core hole is greater than % inch in diameter, the dis- tance from any point on its circumference to the edge of the insert shall be not less than the diam- eter of that core hole. 3.4.3.1. Surface defects— Surface defects other than core holes shall be not greater than y 2 inch in diameter or depth. 3.4.3.2. Insert reinforcements — (applicable only to removable covers) The inserts shall be re- inforced along the entire circumference of their top and bottom edges with sheeting and ad- hesive or presure sensitive tape. This reinforce- ment shall be 2 inches, plus or minus 5/32 inch, in width, when measured in accordance with sec- tions 13 through 17 of ASTM D 1910-64 (Reap- proved 1970) , Standard Methods of Test for Con- struction Characteristics of Woven Fabrics. It shall be applied to the insert so that a minimum of 34 inch is adhered to the top or bottom and the side of the insert. It shall not be possible to sepa- rate the reinforcement from the insert by hand, except by tearing the latex foam. 4. INSPECTION AND TEST PROCEDURES 4.1. Resistance of the cover to mineral oil — Place an 8- by 8-inch specimen, from the cover to be tested, exterior side up, on a wood frame having inside dimensions of 6 by 6 inches, 1 inch in depth. Force the specimen into the frame using a block approximately % inch smaller than the frame in length and width, and rounded at the corners, to form a basin of uniform depth. Tack the edges of the specimen to the frame and re- move the block. Pour mineral oil into the basin to a depth of approximately y 2 mcn an d allow it to remain there for 4 hours. The specimen should be examined for swelling or penetration to the back surface. 4.2. Exceptions to Method 6711 when testing for resistance of the cover to alcohol— The ex- ceptions shall be as follows: (1) The immersion medium shall be a 70 per- cent solution of alcohol. (2) Specimens shall be taken in the warp and in the filling directions and shall be 8 by 4 inches. (3) The immersion time shall be 22 hours. (4) Twenty-four hours after the end of im- mersion, one specimen from both the warp and filling directions shall be folded in half, parallel to its width. The folded edge shall be rolled 10 times with a metal roller, under a load of 5 pounds. (5) The specimens shall be examined after im- mersion and after rolling. 4.3. Exceptions to Method 6711 when testing for resistance of the cover to phenol— The ex- ceptions shall be those indicated in (2), (4), and (5) of 4.2. 4.4. Exceptions to Method 7411 when testing for resistance of the cover to sterilization — The exceptions shall be as follows : ( 1 ) The specimen shall be 12 inches square and shall be folded twice into a square 6 by 6 inches. (2) Twenty-four hours after the fifth period of sterilization, a piece 8 by 6 inches shall be cut from each direction of the specimen and tested for resistance to cracking as specified in (4) of 4.1. 4.5. Exceptions to ASTM D 1203-67 (Method A), when testing plasticizer loss of the cover — The exceptions shall be as follows: (1) The specimen shall be 2 by 2 inches. (2) The specimen shall be heated for 24 hours at a temperature of 212 ± 9 °F (100 ± 5 °C). 5. IDENTIFICATION In order that purchasers may identify prod- ucts conforming to all requirements of this Vol- untary Product Standard, producers and distrib- utors may include a statement of compliance in 4 conjunction with their name and address on prod- uct labels, invoices, sales literature, and the like. The following statement is suggested when suffi- cient space is available: This mattress conforms to the requirements established in Voluntary Product Standard PS 63-75, developed cooperatively with the industry and published by the National Bu- reau of Standards under the Procedures for the Development of Voluntary Product Standards of the U.S. Department of Com- merce. Full responsibility for the conform- ance of this product to the standard is as- sumed by (name and address of producer or distributor) . The following abbreviated statement is sug- gested when available space on labels is insuffi- cient for the full statement: during 1972 a tentative draft of the standard was sent to the Standing Committee for approval. The proposed standard was circulated for acceptance in 1972 and 1973 but failed to gain a consensus. Finally a new proposal was approved by the Standing Committee in August 1974. The new recommended standard was circulated for accept- ance in September 1974. The response to this circulation showed that a consensus among pro- ducers; distributors, and users in accordance with the published procedures was attained. The new edition of the standard was designated Voluntary Product Standard PS 63-75, Latex Foam Mattresses for Hospitals, and became effec- tive on February 3, 1975. Technical Standards Coordinator : George S. Chaconas, Standards Development Services Section, National Bureau of Standards Washington, D.C. 20234 Conforms to PS 63-75, (name and address of producer or distributor) . 6. EFFECTIVE DATE The effective date of this Voluntary Product Standard is the date upon which reference to the Standard may be made by producers, distributors, users and consumers, and other interested parties. Compliance by producers with all of the require- ments of this Voluntary Product Standard may not actually occur until some time after its effec- tive date. Products shall not be represented as conforming to this Voluntary Product Standard until such time as all requirements established in the Standard are met. The effective date of this Standard is February 3, 1975. After this date, products shall not be labeled as conforming to the superseded standard, CS 182-51. 7. HISTORY OF PROJECT Commercial Standard CS 182-51, Latex Foam Mattresses for Hospitals, was developed at the re- quest of the Rubber Manufacturers Association and was published in 1951. In 1962 the Rubber Manufacturers Association requested that the National Bureau of Standards initiate a revision of CS 182-51 under the Pro- cedures for the Development of Voluntary Prod- uct Standards. The proposed standard was ap- proved by the Standing Committee and circulated for acceptance in 1965. Because of a limited re- sponse to that circulation and a conflict over flam- mability requirements, the project to revise the standard was terminated in 1966. In October 1968 the Rubber Manufacturers Associated requested that another attempt be made to revise CS 182-51. On three occasions 8. STANDING COMMITTEE A Standing Committee has been appointed to assist in keeping this Voluntary Product Stand- and up to date. The names and members of the committee are available from the Standards De- velopment Services Section, National Bureau of Standards, Washington, D.C. 20234, which serves as the secretariat of the committee. APPENDIX A. Care of Latex Foam Mattresses Latex foam is porous and should, therefore, be protected from contaminating liquids. If it is necessary to remove the latex foam insert from the cover, it should be protected against pro- longed exposure to direct sunlight, which will cause deterioration. While the latex foam has sufficient tensile strength to withstand ordinary use, it can never- theless be torn by mishandling. Therefore, some care must be taken whenever it is necessary to handle the insert, particularly when it is wet, to avoid mechanical damage. When washing and drying the insert, the tem- perature of the water should be maintained at between 130 °F and 160 °F (54 °C and 71 °C) and the temperature of the dryer kept below 150 °F (65 °C). The following materials are harmless to latex foam : ammonia water, borax, washing soda, soap solution, and synthetic detergents. Any other cleansing agents should be investigated thor- oughly before using. Typical cleansing agents that are harmful include gasoline, carbon tetra- chloride, bleaching solutions, and any acid mate- rial. Care must be taken so that copper and man- ganese-bearing materials do not come in contact with the latex foam insert. For disinfection, the cover or insert may be sprayed, sponged, or soaked with a mild disin- fectant. For sterilization, the cover or insert may be exposed to steam pressures up to 15 psi or to ethylene oxide gas under controlled conditions as recommended by the manufacturers of gas steril- ization equipment. eral Conference on Weights and Measures which met in Paris in October 1960. For assistance in converting U.S. customary units to SI units, see ASTM E 380, ASTM Standard Metric Practice Guide, available from the American Society for Testing and Materials, 1916 Race Street, Phila- delphia, Pa. 19103. The conversion factors for the units found in this Standard are as follows : APPENDIX B The conversion factors and units contained in this appendix are in accordance with the Inter- national System of Units (abbreviated SI for Systeme International d'Unites). The SI was defined and given official status by the 11th Gen- 1 inch = 25.4 millimeters 1 foot = 0.3048 meter 1 pound (force) = 4.448 newtons 1 pound per square inch = 6894.76 pascals (newtons per square meter) t c = (t P - 32)/1.8 where t c = temperature in degrees Celsius where t F = temperature in degrees Fahrenheit NBS TECHNICAL PUBLICATIONS PERIODICALS JOURNAL OF RESEARCH reports National Bureau of Standards research and development in physics, mathematics, and chemistry. 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