(1) For the purposes of this Part and Schedule 1, the concentration of alcohol
present in a person's breath or blood may be expressed as follows--
(a) in the
case of a sample of breath that is measured by a breath analysing instrument
or other breath testing device that provides a reading or result by reference
to alcohol present in the breath--the amount of alcohol in grammes in 210
litres of breath,
(b) in the case of a sample of breath that is measured by a
breath analysing instrument or other breath testing device that provides a
reading or result by reference to alcohol present in the blood--the amount of
alcohol in grammes in 100 millilitres of blood,
(c) in the case of a sample
of blood--the amount of alcohol in grammes in 100 millilitres of blood.
(2)
An amount of alcohol in grammes present in breath when measured by reference
to 210 litres of breath is equivalent to the same amount of alcohol in grammes
present in blood when measured by reference to 100 millilitres of blood.
(3)
Accordingly, any offence under this Part relating to the presence of a
specified concentration of alcohol in a person's breath or blood at the time
of the occurrence of a particular event is a single offence regardless of
whether the concentration of alcohol concerned is measured by reference to the
amount of alcohol present in breath or in blood (or both).