46 C.F.R. § 62.35-50
Tabulated monitoring and safety control requirements for specific systems.
Cite as 46 C.F.R. § 62.35-50 (2026)
The minimum instrumentation, alarms, and safety controls required for specific types of systems are listed in table 1 to § 62.35-50. The ABS Marine Vessel Rules (incorporated by reference; see § 62.05-2) required for engineering systems are also listed in table 1 to § 62.35-50.
(a) Safety limit controls must be provided in navigating bridge primary propulsion control systems. See § 62.35-5(c).
(b) Safety trip controls and alarms must be provided for all main boilers, regardless of mode of operation. See § 62.35-20(a).
(c) Loss of forced lubrication safety trip controls must be provided for main propulsion turbines and main propulsion diesel engines.
(d) Override of overspeed and loss of forced lubrication pressure safety trip controls must not be provided for main propulsion or generator steam or gas turbines, or diesel engines. See § 62.35-5(e)(2).
(e) Transfer interlocks must be provided for main propulsion systems capable of remote and local control.
(f) Semiconductor controlled rectifiers must have current limit controls.
(g) Interlocks must be provided to prevent the starting of engines or turbines while the jacking or turning gear, if installed, is engaged. See § 62.25-5(a).
(h) Main and remote-control stations, including the navigational bridge, must provide visual and audible alarms in the event of a fire in the main machinery space.
(i) Minimally attended and periodically unattended machinery plants must be provided with a personnel alarm that annunciates on the bridge if not acknowledged by the watch engineer. See § 62.50-20(b)(1).
(j) All automatic controls and alarms must be failsafe to the least critical consequence for the particular system. See § 62.30-1.
(k) The operating or tripped status of vital auxiliary boilers must be indicated at the ECC. See part 63 of this subchapter.
Table 1 to § 62.35-50—Minimum System Monitoring and Safety Control Requirements for Specific Systems
System
Service
Instrumentation
Alarm
Safety control
See also
paragraph
Main (Propulsion) boiler
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
(a)
Burner seating
Failure
Burner auto trip
(b)
Trial for ignition
Status
Failure
Burner auto trip
(b)
Manual trip
(b)
Low fire interlock
Status
Program control interlock
Status
Main (Propulsion steam) turbine
ABS Marine Vessel Rules Part 4-9-6 table 2
ABS Marine Vessel Rules Part 4-9-6 table 2
ABS Marine Vessel Rules Part 4-9-6 table 2
Manual trip
(c), (d)
Main propulsion, diesel
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
ABS Marine Vessel Rules Part 4-9-6 tables 1A, 1B and 5A
Manual trip
(c), (d)
Main propulsion, remote control
Failure
Manual trip
Auto safety trip override
Activated
Starting power
Pressure (voltage)
Low
Limit
(a)
Location in control
Status
Override
(c)
Shaft speed/direction/pitch
See § 113.37 of this chapter.
See § 113.37 of this chapter.
See § 113.37 of this chapter.
Clutch fluid
Pressure
Low
Main propulsion, electric
(1)
ABS Marine Vessel Rules Part 4-9-6, tables 4A and 4B
ABS Marine Vessel Rules Part 4-9-6, tables 4A and 4B
ABS Marine Vessel Rules Part 4-9-6, tables 4A and 4B
ABS Marine Vessel Rules Part 4-9-6, tables 4A and 4B
(f)
Main propulsion, shafting
Stern tube oil tank level
Low
Line shaft bearing
Temperature
High
Forced lubrication Pressure
Low
Main propulsion, controllable pitch propeller
Hydraulic oil
Pressure
High, Low
Temperature
High
Generators
Ship service
ABS Marine Vessel Rules Part 4-9-6, table 6
ABS Marine Vessel Rules Part 4-9-6, table 6
Starting pressure/voltage
Low
Tripped
Emergency
2
Turbogenerator
ABS Marine Vessel Rules Part 4-9-6, table 6
ABS Marine Vessel Rules Part 4-9-6, table 6
ABS Marine Vessel Rules Part 4-9-6, table 6
Manual trip
Diesel
ABS Marine Vessel Rules Part 4-9-6, table 6
ABS Marine Vessel Rules Part 4-9-6, table 6
ABS Marine Vessel Rules Part 4-9-6, table 6
(d)
Manual trip
Auxiliary boiler
Run
Trip
(k)
Gas turbine
3
ABS Marine Vessel Rules Part 4-9-6, Tables 3 and 6
ABS Marine Vessel Rules Part 4-9-6, Tables 3 and 6
ABS Marine Vessel Rules Part 4-9-6, Tables 3 and 6
ABS Marine Vessel Rules Part 4-9-6, Tables 3 and 6
(d)
Engines and turbines
Jacking/turning gear
Engaged
(g)
Fuel oil
ABS Marine Vessel Rules Part 4-9-6, tables 5A and 6
ABS Marine Vessel Rules Part 4-9-6, tables 5A and 6
ABS Marine Vessel Rules Part 4-9-6, tables 5A and 6
Remote/auto fill level
High
Auto trip or overflow arrangement
Hi. press. leakage level
High
Bilge
Pump remote control
Run
Pump auto control
Run
Excessive operations
Level
High/location
Machinery space Class 3 (power-operated) watertight doors
Open/closed
Fire detection
Machinery spaces
Space on fire
(h)
Fire main
Pressure
Low
Personnel
Deadman
Fail to acknowledge
(i)
General, control and alarm systems
Power supply
Available (pressure)
Failure (low)
System function
Failure
(j)
Console air conditioning
Failure
Built in test equipment
Active
Sequential interlock
Activated
Safety control
Activated
Auto trip/limit
(j)
Redundant auxiliary, system, power supply
Status
Auto transfer
1
See subparts 111.33 and 111.35 of this chapter.
2
See subparts 112.45 and 112.50 of this chapter.
3
See § 58.10-15(f) of this subchapter.
[CGD 81-030, 53 FR 17838, May 18, 1988; 53 FR 19090, May 26, 1988, as amended by USCG-2000-7790, 65 FR 58461, Sept. 29, 2000; USCG-2003-16630, 73 FR 65190, Oct. 31, 2008]
- Cross-references to the CFR
- 113.3758.10-1562.05-262.25-562.30-1.62.35-2062.35-562.35-5062.35-50.62.50-20