i think that maybe the origanal question may have been missunderstood by some. as has been pointed out by clive the policy at the moment is to request a breath test from all drivers involved in a R.T.A then it is quit likely that even a non drinker will be asked to provide a specimen.
as i understand the law you [U]can not[U] refuse a road side test for any reason. to do so will lead to your arrest.once at the police station then further enquiries will be made in regard to your reasons for refusal. in my opinion this does raise some questions regarding this policy, as i do not see the justification for requesting a specimen if there are no obvious indications that the person has been drinking.
i sympathise with the questioner as i am quite sure that he has no wish to be arrested for something he has no control over.

