Page 34 - Safety Risk Management for Medical Devices

The Basics 13

Initiating Event 2 Event 3 Hazard Harm
event

Hazardous
situation
Figure 3.1 Hazard Theory.

It is a very good idea to consult with other departments such as sales, marketing
and clinical staff to get insights into how the device might get misused in the field.

3.2 HAZARD THEORY

In order to receive Harm, there must be exposure to Hazard(s). Fig. 3.1 illustrates a
model that is called Hazard Theory. The model states that an initiating event starts
a progression of events that culminate in a Hazard. The Hazard is the last stop in the
chain of events that lead to the Hazard. Unless there is exposure to the Hazard(s),
there can be no Harm. Of course, Harm can be of various degrees of severity; any-
where from negligible to catastrophic.
In the BXM method the complete spectrum of Harm is considered. That is, given
a Hazardous Situation, everything from nothing to death is considered. Therefore, it
can be said that once the Hazardous Situation has been achieved, the probability of
receiving Harm is 100%.

3.3 SYSTEM TYPES

The Systems that are subjected to the risk management process can be classified into
two categories:

a. Integral Systems
These are Systems that are observable as one integral piece from the perspective
of the user. They do not require any assembly or integration by the user.
Example: a blood glucose monitor.