What is machinery space?

Unattended Machinery Space,or UMS,is a way of operating the automatically controlled machinery of a vessel(e.g. ship);UMS Mode means that, instead of continuous watchkeeping IN the engine room , a DUTY cycle of usually 24 hours is used,during which the duty engineer is free to stay anywhere onboard the ship,provided he is in permanent control over a signalling device(control board).A class "A" of automatization of the ship is a must.