Translate the following English sentence to French:
"From discussions at various company headquarters it has emerged that EMAS has an internal impact and that workforces are playing a far greater part in protecting the environment, but the time has now come to improve the external impact of the system."
Des entretiens dans les entreprises ont montré que l' EMAS a une efficacité interne, à savoir que le personnel participe de plus en plus à la protection de l' environnement, mais l' efficacité extérieure doit être améliorée.