{"id":389405,"date":"2024-10-20T03:49:53","date_gmt":"2024-10-20T03:49:53","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bs-en-iso-18369-42017-2\/"},"modified":"2024-10-26T07:01:51","modified_gmt":"2024-10-26T07:01:51","slug":"bs-en-iso-18369-42017-2","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bs-en-iso-18369-42017-2\/","title":{"rendered":"BS EN ISO 18369-4:2017"},"content":{"rendered":"
This document specifies the methods of testing the physicochemical properties of contact lens materials. These are extraction, rigid lens flexure and breakage, oxygen permeability, refractive index and water content.<\/p>\n
PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
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2<\/td>\n | National foreword <\/td>\n<\/tr>\n | ||||||
4<\/td>\n | European foreword <\/td>\n<\/tr>\n | ||||||
6<\/td>\n | Foreword <\/td>\n<\/tr>\n | ||||||
9<\/td>\n | 1 Scope 2 Normative references 3 Terms and definitions 4 Physicochemical properties of contact lenses 4.1 Repeatability, test methods and units of measure <\/td>\n<\/tr>\n | ||||||
10<\/td>\n | 4.2 Extractables 4.2.1 General 4.2.2 Principle 4.2.3 Apparatus <\/td>\n<\/tr>\n | ||||||
11<\/td>\n | 4.2.4 Reagents <\/td>\n<\/tr>\n | ||||||
12<\/td>\n | 4.2.5 Test samples 4.2.6 Test procedure 4.2.7 Calculation of results <\/td>\n<\/tr>\n | ||||||
13<\/td>\n | 4.2.8 Test report 4.3 Rigid lens flexural deformation and rupture 4.3.1 Principle 4.3.2 Sampling <\/td>\n<\/tr>\n | ||||||
14<\/td>\n | 4.3.3 Preparation of samples 4.3.4 Apparatus <\/td>\n<\/tr>\n | ||||||
16<\/td>\n | 4.3.5 Procedure 4.3.6 Test result <\/td>\n<\/tr>\n | ||||||
17<\/td>\n | 4.4 Oxygen permeability 4.4.1 General 4.4.2 Common elements of the methods <\/td>\n<\/tr>\n | ||||||
18<\/td>\n | 4.4.3 Polarographic method <\/td>\n<\/tr>\n | ||||||
26<\/td>\n | 4.4.4 Normalization of the corrected oxygen permeability using reference lenses <\/td>\n<\/tr>\n | ||||||
27<\/td>\n | 4.4.5 Test report 4.5 Refractive index 4.5.1 General 4.5.2 Abbe refractometer <\/td>\n<\/tr>\n | ||||||
28<\/td>\n | 4.5.3 Test samples 4.5.4 Procedure <\/td>\n<\/tr>\n | ||||||
29<\/td>\n | 4.5.5 Expression of test results 4.5.6 Test report <\/td>\n<\/tr>\n | ||||||
30<\/td>\n | 4.6 Water content 4.6.1 General 4.6.2 Gravimetric determination of water content\/absorption by loss on drying using an oven <\/td>\n<\/tr>\n | ||||||
32<\/td>\n | 4.6.3 Test report 5 Test report <\/td>\n<\/tr>\n | ||||||
33<\/td>\n | Annex A (informative) Determination of oxygen permeability using the coulometric method <\/td>\n<\/tr>\n | ||||||
40<\/td>\n | Annex B (informative) Determination of water content by refractive index <\/td>\n<\/tr>\n | ||||||
41<\/td>\n | Annex C (informative) Calculation of oxygen permeability of hydrogel contact lenses based on water content <\/td>\n<\/tr>\n | ||||||
42<\/td>\n | Annex D (informative) Measurement of refractive index using a prism coupling device <\/td>\n<\/tr>\n | ||||||
44<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Ophthalmic optics. Contact lenses – Physicochemical properties of contact lens materials<\/b><\/p>\n |