marker inversion

Hi everyone, I'm new on this site and it looks very interersting. I'm graduated from a french school and I am working in an anglophone organisation. I notice that every techs graduated from a anglophone school in Montréal are inversing there markers when they are doing PA incidences to make it look the right way when the image will be flipped in AP.  I wouldl like to have your opinion on this or tell me what are the convention in your hospital.  Thank you !  Florence