Condition YOKE provides a greater degree of watertight integrity than condition XRAY, but to a lesser degree than the maximumcondition.  YOKE is normally set at sea and in port during wartime. When Condition Yoke is set, all fittings marked with black Xs and Ys, Circle X and Circle Y are closed. A modified condition YOKE is sometimes used at sea when cruising independently in good weather and calm seas and in port in peacetime. In the modified condition, YOKE fittings above the waterline are left open to improve ventilation and habitability. All other XRAY and YOKE fittings are closed.