Page 235 - Safety Risk Management for Medical Devices

214 Safety Risk Management for Medical Devices

that comes into contact with the patient for the purpose of performing its clinical
function. In some cases, a medical device may come into contact with the patient/
user but not for the purpose of performing the device’s clinical function. Such contact
may be a source of Hazards. IEC 60601-1 [8] defers to ISO 14971 [3], the determina-
tion of how to treat the nonapplied parts of the device that come into contact with
the patient/user.
The concept of Essential Performance was defined in Section 3.1 and elaborated in
Chapter 28, Basic Safety and Essential Performance. IEC 60601-1 [8] expects the manu-
facturer to identify the Essential Performance of the medical device. There are many spe-
cialized test houses who perform IEC 60601-1 [8] compliance testing for manufacturers.
As input to the test house, besides samples of the medical device, the test house expects
the manufacturer to identify the Essential Performance of the device.
A point to keep in mind about using compliance with IEC 60601-1 [8] as the
foundation of claim of risk acceptance, is that IEC 60601-1 [8] itself is not a Risk
Control. The design features that enable passing the IEC 60601-1 [8] tests, are the
Risk Controls. Therefore the 60601-1 [8] passing test results are the objective evi-
dence that the Risk Controls are effective.

29.2 INTERACTION WITH ISO 10993-1

ISO 10993 is a series of Standards numbered ISO 10993-1 to ISO 10993-22. ISO
10993-1 [15] is about biological evaluation and testing of medical devices within a
risk management process. ISO 10993-2 to ISO 1-003-22 are each dedicated to a spe-
cial aspect of biocompatibility. The aim of this series of Standards is the protection of
humans from biological risks due to the use of medical devices.
The range of biological responses that are considered as adverse, i.e., Hazards, is quite
broad and complex, and vary from person to person. They include: cytotoxicity, sensiti-
zation, irritation, hemocompatibility, pyrogenicity, carcinogenicity, and genotoxicity.
ISO 10993-1 [15] does not intend to provide a rigid battery of tests, including
pass/fail criteria that can be used by a manufacturer to demonstrate biocompatibility.
Instead, the standard offers guidance on ways of determining what testing is needed
with aim of achieving an acceptable level of risk for the benefits that the medical
device offers.
ISO 10993-1 [15] considers biological risk management as part of the overall pro-
cess of management of safety risks to humans in accordance to ISO 14971 [3,7].
Conduct of biological evaluations serves to meet the requirements of both ISO 14971
[3,7] and ISO 10993-1 [15].
Execution of biological evaluations requires planning. The biological evaluation
plan is a part of the overall risk management plan. It’s possible to combine the two
plans under one cover. The biological evaluation plan must include arrangements for