BS EN ISO 8321-2-2000 Ophthalmic optics . 一 Specifications for material, optical and dimensional properties of contact ] lenses – Part 2: Single-vision hydrogel contact lenses.
This part of ISO 8321 specifies requirements for hydrated single-vision hydrogel contact lenses including tolerance limits for material, optical and dimensional properties. A method for presenting the specification of contact lenses is described in annex A.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of ISO 8321. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of ISO 8321 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards.
ISO 8320-1 :__1), Contact lenses and contact lens care products — Vocabulary — Part 1: Contact lenses.
ISO 8599:1994, Optics and optical instruments — Contact lenses — Determination of the spectral and luminous transmittance.
ISO 9337-1:1999, Contact lenses — Determination of back vertex power — Part 1: Method using focimeter with manual focusing.
ISO 9338:1996, Optics and optical instruments — Contact lenses — Determination of the diametes’s.
ISO 9339-2:1998, Optics and optical instruments — Contact lenses — Determination of thickness — Part 2:
Hydrogel contact lenses.
ISO 991 3-1 :1996, Optics and optical instruments — Contact lenses — Part 1: Determination of oxygen permeability and transmissibility with the FA 7T method, ISO 9914:1995, Optics and optical instruments — Contact lenses — Determination of refractive index of contact lens materials.
ISO 10338:1996. Optics and optical instruments — Contact lenses — Determination of curvature.
ISO 10339:1997, Ophthalmic optics — Contact lenses — Determination of water content of hydrogel lenses. ISO 10344:1996. Optics and optical instruments — Contact lenses — Saline solution for contact lens testing.
3 Terms and definitions
For the purposes of this part of ISO 8321, the terms and definitions given in ISO 8320-1 apply.
4 Requirements for dimensions and optical properties
4.1 Test methods
Each dimension and physical or optical property specified shall be determined using a test method with a measurement tolerance limit better than one-hall of the tolerance limit specified tor the property.
The International Standards which specify the relevant test methods are listed in Tables 1 and 2.
4.2 Conditioning of contact lenses prior to testing
Contact lenses shall be conditioned in accordance with the relevant test method.
4.3 Tolerances
When tested as described in 4.1 and 4.2 the dimensional and optical properties shall be as specified, within the
appropriate tolerance limits given in Table 1 and the material physical pi’operties as given in Table 2.
5 Requirement for finish
5.1 Criteria
Acceptance and failure criteria for inclusions, surface imperfections, edge contour and finish shall be documented
by the manufacturer.
5.2 Inclusions and surface finish
When examined at xlO magnification in standard saline solution according to ISO 10344, the contact lens shall not exhibit any inclusions or surface imperfections which could interfere with its intended functional use.
5.3 Edge contour and finish
When examined at x7 magnification, the contact lens edge shall meet the quality characteristics indicated by the manufacturer with respect to shape, smoothness and polish.BS EN ISO 8321-2 pdf download.