(ISO international Standard 7741 INTE RNATIONAL ORGANIZATION FOR STANDARDIZATION MEKIYHAPOAHAH OPTAHW3ALWH TIO CTAHAAPTW3AUWVORGANISATION INTE RNATIONALE DE NORMALISATION Instruments for surgery - Scissors and shears Generai requirements and test methods Instruments chirurgicaux -- Ciseaux et cisailles -- Specifications generales et methodes d'essai First edition -- 1986-02-01 UDC 615.472.4 Ref. No. 1S0 7741-1986 (E) IS() 7741-1986 (E) Descriptors : medicai equipment, surgicai equipment, surgicai scissors, specifications, tests, periormance tests Price based on 3 pages Foreword ISO (the International Organization for Standardization) is a worldwide federation of nationai standardis bodies (isO member bodies). The work of preparing internationai Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technica! committee has been estahlished has mentai and non-governmentai, in liaison with isO, also take part in the work. Draft internationai Standards adopted by the technicai committees are circulated to the member bodies for approval before their acceptance as International Standards by the IsO Council. They are approved in accordance with ISO procedures reguiring at ieast 75 % approvai by the member bodies voting. Surgical instruments. Users shouid note that all internationai Standards undergo revision from time to time latest edition, unless otherwise stated. International Organization for Standardization, i986 Printed in Switzerland ISO 7741-1986 (E) INTERNATIONAL STANDARD Instruments for surgery -- Scissors and shears General requirements and test methods Scope and field of application 3.2 Rivet or screw 1 The rivet or screw shall be made of stainless steel chosen, at This international Standard specifies general requirements and the discretion of the manufacturer, from the grades specified in corresponding routine test methods for scissors and shears ISO 683/13. which are used in surgery. Requirements 4 2 References Is0 683/13, Heat-treated steels, alloy steels and free-cutting 4.1 Heat treatment and hardness for component steels - Part 13: Wrought stainless steels. parts, excluding rivets and screws ISO 4957, Tool steels. 4.1.1 Heat treatment Iso 6507/1, Metallic materials - Hardness test - Vickers test The component parts of the instruments shall be heat treated Part1:HV5toHV100. under suitable conditions to ensure compliance with the ISo 6508, Metallic materials - Hardness test - Rockwell test requirements of 4.1.2 and 4.1.3 for the material used. Scales A, B, C, E, F, G, H.1) Iso 7153/1, Instruments for surgery -- Metallic materials - 4.1.2 Hardness for instruments without tungsten Part 1: Stainless steel. carbide or stellite inserts The Rockwell hardness of the finished instruments shall be 3Material within the range from 50 HRC to 58 HRC (approximately equivalent to Vickers hardness range from 530 HV to 670 HV) Component parts when tested in accordance with iso 6508 and ISo 6507/1 3.1 respectively. Opposite blades shall not vary in hardness by The component parts of the instruments, excluding the rivet or more than 4 units on the Rockwell C hardness scale. screw, shall be made of stainless steel in accordance with tabte 1. 4.1.3 Hardness for instruments with tungsten carbide or stellite inserts Table 1 --- Material -- Steel grades The Vickers hardness of the tungsten carbide or stellite inserts Steel grade shall be at least 710 HV 10 when tested in accordance with Grade No. according to Reference letter ISO 6507/1. The inserts of opposite blades shall not vary in hard- according to ISO 7153/1 ISO 4957 ISO 683/13 B* The Rockwell hardness of the body of the instruments with 27* 4* tungsten carbide or stellite inserts shall be 40 HRC min. 28 5 4.2 Corrosion resistance 4.2.1 Scissors and shears made of steel grade C Only for scissors and shears with tungsten carbide or stellite inserts. Two test methods are specified for determining corrosion Special atten