Hello, Is it safe for a baby to sleep in a room that has no windows?

Red Nose does not have any specific information about a link to Sudden Unexpected Death in Infancy (SUDI) & a room without windows.
It is generally recognised that circulating air, over time, is important in a sleep environment for all.
Some families will use a ceiling fan to achieve this, others leave door open to allow air to circulate.

Do you have a specific concern about the impact of no windows?