SPECIMEN EXAMINATION FOR CHIEF MATE 



73 



Describe briefly the usual procedure 

 followed in cleaning and gas-freeing oil 

 tanks. 



When seamen are working upon a 

 mast near radio transmitting antennae, 

 what precautions should be taken? 



What precautions should be observed 

 to prevent shock of personnel, when 

 portable electric lights, or appliances 

 are used? 



In taking bunker oils, or loading or 

 discharging oil cargo, what precautions 

 should be taken to prevent harbor pol- 

 lution in the event of a spill on deck? 



If through an accident, oil is spilled 

 into harbor waters, how can pollution 

 be minimized? 



What precautions are advisable when 

 padeyes, cleats, lashings, or other fit- 

 tings are so located on the decks that 

 personnel may trip or stumble over 

 them in the dark? 



Why is a reciprocating or rotary type 

 pump nonnally employed for stripping 

 tanks of liquid? 



Describe how planks used for staging 

 should be tested in order to determine 

 that they are strong enough to carry 

 their load with an ample safety factor. 



To determine if a tank is gas free: 



(a) What instrument is used? 



(b) In circumstances where a gas 

 chemist is unavailable, what precau- 

 tions must be observed in using such in- 

 struments? 



What precautions should be observed 

 when using carbon tetrachloride fire ex- 

 tinguishers, or when employing carbon 

 tetrachloride for cleaning purposes? 



What is the "carrier" bearing fitted 

 on most modern vessels at the rudder? 



If a vessel is moored as sketched, 

 with a camel well aft between the ship 

 and dock, what would be the effect of 

 heaving on the head lines with the stern 

 line taut? 



Referring to the sketch : 



(a) When buffer springs are fitted 

 on a quadrant type steering gear, why 

 is it important that the quadrant be free 

 to move on the rudder stock? 



(b) Under what circumstances 

 would you use a key in the keyways 

 marked "B"? 



Note : Tension and compression on springs ex- 

 aggerated in sketch for clarity. 



What materials are usually employed 

 for rudder gudgeon bushings and how is 

 the bushing clearance determined? 



Describe the methods used to repair 

 leaking rivets. 



What precautions should be taken 

 when personnel are obliged to traverse 

 decks over the top of deck cargo? 



How could you stop a leak caused by 

 a rivet dropping out of the shell below 

 the water line? 



A crack appears on an internal bulk- 

 head of a vessel at sea. What measure 

 could you take to stop the crack from 

 lengthening? 



When oil is discovered in a vessel's 

 bilge wells at the time soundings are 

 taken, what steps should be taken to 

 prevent oil pollution of coastal waters? 



690-515 O - 63 - 6 



