Paragraph 3.1.1 F1

The effect of an electromagnetic disturbance on a gas meter shall be such that:

• — the change in the measurement result is no greater than the critical change value as defined in paragraph 3.1.3, or

• — the indication of the measurement result is such that it cannot be interpreted as a valid result, such as a momentary variation that cannot be interpreted, memorised or transmitted as a measuring result.