In Genesis, the LORD shut Noah inside the Ark after Noah and his family entered.
Genesis 7:16 says that the animals entered the ark in pairs, and that the LORD shut Noah in. The wording places the closing of the door under divine action rather than describing Noah or one of his sons securing it from inside.
The detail comes immediately before the Flood waters rise. It marks the transition from preparation to judgment and emphasizes that Noah’s household is protected within the vessel. The same chapter identifies Noah, his wife, their three sons, and their sons’ wives as the human occupants.
Translations differ in how they render the divine name: many English versions use “the LORD,” while others may use “Yahweh” or another equivalent. The answer refers to the subject of the Hebrew wording, not to a human member of Noah’s family.