The officers who responded to a Triple-000 call early this morning at Portland carried the three people from the home. All three were overcome with carbon monoxide, with one of then already unconscious when police arrived.

As a result of the incident five people, including the two police officers involved in the rescue, were hospitalised with suspected carbon monoxide poisoning.

Chifley Local Area Commander, Supt Michael Robinson said emergency services were called to a home on Back Cullen Road at Portland about 12.30am, Thursday, where they found one man unconscious and two needing medical assistance.

The two police officers attached to Chifley Local Area Command carried the occupants from the home with a 69-year-old woman and two men aged 72 and 79 taken to Lithgow Hospital.

The 72-year-old man was later airlifted to Nepean Hospital.

After rescuing the three elderly people, the two officers - a sergeant and senior constable - were also taken to hospital suffering carbon monoxide poisoning from a barbeque inside the home.

The two police officers were released from hospital this morning while the occupants of the home are expected to be released later today.

Supt Robinson commended the work of his officers, saying without their efforts, "police would have certainly been dealing with a triple fatality" today.

He said the police response, and the officers "quick decisive actions" undoubtedly saved three lives.

Supt Robinson said the alarm was raised by someone from inside the house, who was already overcome with fumes, and didn't understand what was going on. He said the caller was in a very confused state and commended the two police officers on the bravery.