46 CFR §153.283

1. (a)Except as described in this section, a cargo line must have a deck operable, manual stop valve:
   1. (1)In each tank which the line serves; and
   2. (2)At each cargo hose connection point.
2. (b)The valve required by paragraph (a)(1) of this section may be in a cargo pumproom at the pumproom bulkhead if the cargo tank the cargo line serves is adjacent to the pumproom.
3. (c)The valve required by paragraph (a)(1) of this section may be on the weatherdeck if:
   1. (1)The weatherdeck is the top of the tank;
   2. (2)The line goes through the weatherdeck into the tank; and
   3. (3)The valve is at the point where the line penetrates the weatherdeck.
4. (d)The valve required by paragraph (a)(1) of this section may be outside the tank if:
   1. (1)The tank is an independent tank; and
   2. (2)The valve is at the point where the line penetrates the tank.
5. (e)The discharge line of an intank cargo pump need not have the valve required by paragraph (a)(1) of this section.
6. (f)If the cargo exerts a gravity head pressure on a valve required by this section, the valve must be a positive shutoff valve that meets § 56.50-60(d) of this chapter.