BS ISO 19351:2019 pdf download – Fallopian rings — Requirements and test methods
4 Requirements
4.1 Quality verification
Fallopian rings are mass produced articles manufactured in very large quantities. Inevitably, there will be some variation between individual rings, and a small proportion of rings in each production run might not meet the requirements of this document. Further, the majority of the test methods described in this document are destructive. For these reasons, the only practicable method of assessing conformity with this document is by testing a representative sample from a lot or series of lots. Basic sampling plans are given in ISO 2859-1. Reference should be made to ISO/TR 8550 (all parts) for guidance on the use of acceptance sampling system, scheme or plan for the inspection of discrete items in lots. When on-going verification is required of the quality of fallopian rings, it is suggested that, instead of concentrating solely on evaluation of the final product, attention is also directed at the manufacturer’s quality system. It should be noted that ISO 13485 covers the provision of an integrated quality system for the manufacture of medical devices. Sampling plans shall be selected to provide an acceptable level of consumer protection. Suitable sampling plans are given in Annexes A and B.
a) Annex A describes sampling plans based on ISO 2859-1 and is most applicable to manufacturers or purchasers assessing the conformity of a continuing series of lots. The full level of consumer protection available depends upon the switch to tightened inspection if deterioration in quality is detected. The switching rules, described in ISO 2859-1:1999, Clause 9, cannot offer their full protection for the first two lots tested but become progressively more effective as the number of lots in a series increases. Use the sampling plans in Annex A when five or more lots are being tested.
b) Annex B describes sampling plans, based on ISO 2859-1, that are recommended for the assessment of isolated lots. The sampling plans in Annex B provide approximately the same level of consumer protection as those given in Annex A when used with the switching rules. It is recommended that these sampling plans are used for the assessment of fewer than five lots, for example in cases of dispute, for referee purposes, for type testing, for qualification purposes or for short runs of continuing lots. It is necessary to know the lot size in order to derive the number of fallopian rings to be tested from ISO 2859-1. The lot size will vary between manufacturers and is regarded as part of the process and quality controls used by the manufacturer. If the lot size is not known or cannot be confirmed by the manufacturer, then a lot size of 10,000 fallopian rings shall be assumed for determining the sample sizes for testing.
4.2 Physical requirements
4.2.1 Dimensions Fallopian rings are tested for the inner diameter and outer diameter in accordance with Annex C and shall conform to the requirements given in Figure 1. Cut rings shall be free from fibrous protrusions at the outer and inner surface. Angle of cut shall be at 90° (≤5° angulations is allowed).
4.2.2 Tensile properties
Fallopian rings tested in accordance with Annex D for the tensile properties shall conform to the requirements stated below.
a) The force at break shall be ≥20,50 N.
b) Elongation at force at break shall be ≥560 %.
4.2.3 Loading force on ring applicator
Fallopian rings tested in accordance with Annex E for the force of loading on ring applicator shal conform to the requirement stated below.
The force required to load fallopian rings on the ring applicator shall be ≤35 N.
4.2.4 Elastic memory
Fallopian rings tested in accordance with Annex F for the elastic memory shall conform to the requirement stated below.
The recovery of the inner diameter shall be such that the increase in the inner diameter ≤25 % of the original diameter.BS ISO 19351 pdf download.