Hi there, I am wondering about weighted sleep suits. Are they recommended for safe sleep? could this be a hazard or unsafe for infants?

Red Nose recommends using blankets, sleeping bags & any bedding that are light weight & tucked in to reduce the risk of baby’s head & face being covered.
If blankets are being used instead of a safe sleeping bag, it is recommended to place your baby with his or her feet at the bottom of the cot, using layers of lightweight blankets that can be added or removed easily according to the ambient feel of the room. Tuck blankets in firmly so they cannot become loose and cover your baby’s head and face during sleep.
https://rednose.org.au/article/how-much-bedding-does-baby-need

Weighted blankets & sleeping bags are not recommended.
Weighted sleeping sacks, like weighted blankets, are unsafe for babies. These products can compress a baby’s chest, leading to a possible lack of oxygen. Weighted sleeping sacks can also cause overheating - a well-known risk factor for SIDS.

There is much research into the vulnerability of babies and children in the sleep environment, particularly with regard to their airways. We know that babies, in particular, have smaller and more easily compressed airways, a more easily compressed chest wall, and less respiratory stamina than older children and adults.

Babies have died due to pressure directly on or against their chests. This is because the pressure inhibits full expansion of the chest and the abdominal movement required for healthy breathing.

There is very little research on the safety aspects of weighted blankets or sleeping bags for babies, particularly in the context of sleep safety in babies and children.
https://rednose.org.au/article/weighted-blankets

Soft toys & comforters should only be used with the same recommendations. eg any comforter (toy or blanket) that is large &/or heavy should be avoided as they may compress baby’s chest & make it difficult & compromise breathing.
Keep the cot free of large soft toys, pillows, bumpers, activity centres and anything else that could be ‘stacked’ to assist a young child/toddler to climb out of the cot.
https://rednose.org.au/article/can-my-baby-have-a-soft-toy