Hi there, i have a 4 week old newborn and am aware it is recommended that newborns sleep in the parents room for the first 6 to 12 months. However, I will be returning to work and the father will be the primary carer, so the plan was that our newborn would sleep with just the father in the room. Is it recommended that the mother is in the same room or would it be ok for just the father to be in the room? Thank you

Red Nose recommends Room Sharing, for all sleeps, for the first 6 months as part of reducing the risk of Sudden Unexpected Death in Infancy (SUDI)
However, many parents are unable to room share for various reasons.
The recommendation is related to adults, either &/or mother or father.

Red Nose has the following information (in part)
Parents are not expected to observe their baby constantly. 
If your baby is sleeping in a separate room check baby regularly to ensure that the baby remains on the back and the head and face remain uncovered (as baby grows beyond 5-6 months they will move around the cot and roll over; settle baby to sleep on their back but let them find the sleep position they feel most comfortable in. 

A safe cot and safe sleep environment is still necessary for babies older than 5-6 months)
The protective effect of room sharing can be partially explained by increased adult supervision and observation of the baby.
Room sharing with baby | Red Nose Australia