CBC News has learned that the Office québécois de la langue française (OLF) is investigating Montreal's ambulance service for dispatching English-only information to emergency workers.
Some crews with Urgences Santé have complained they get too much crucial information in English, regardless of whether they speak or understand the language.
The problem has created a situation where dispatchers are increasingly asked to translate for ambulance workers who don't understand English instructions.
About one-third of calls to the Urgences Santé dispatch centre are in English, and medical responders who handle calls must be bilingual.
But ambulance workers aren't required to be bilingual.
"The workers have the right to conduct their activities in French in Quebec," said OLF spokesman Martin Bergeron.WATCH Nancy Wood's report here