Oil traces have been found in the condensate tank of an auxiliary boiler: describe the procedure to trace the source and list the contamination with reasons and safety precautions?

flowchart TD
    A[Oil traces in condensate tank] --> B{Isolate boiler\nstop fuel & steam}
    B --> C[Sample condensate & feedwater]
    C --> D[Inspect: burner front\nfuel-oil system\nheat exchangers\nglands]
    D --> E{Test for oil\nin feedwater/steam}
    E -->|Oil found| F[Identify leak path]
    E -->|No oil| G[Check sampling\nre-test]
    F --> H[Isolate section\npressure test]
    H --> I[Rectify leak]
    I --> J[Flush system\nrestore oil-free condition]
    J --> K[Restart with monitoring]

• Context: Oil in auxiliary-boiler condensate is a fire and explosion hazard; it fouls heat-transfer surfaces and can cause carryover into steam
• Part (a) procedure: Isolate boiler → sample condensate → inspect feed system, fuel-oil system, burner front, heat exchangers → test for oil in feedwater and steam → identify leak path → verify by isolation and pressure test
• Part (b) contamination: Fuel oil from burner leaks or atomising failures; lube oil from gland leaks or heat-exchanger failures; hydraulic oil from control systems
• Reasons: Failed seals/gaskets, cracked pipes, improper burner coupling, oil heater relief valve discharge, save-all overflow
• Precautions: Screens and save-alls under oil units, quick-closing master oil valves at furnace fronts, closed-circuit relief for oil heaters, regular sampling of feedwater and condensate, immediate shutdown on oil detection
• Instrument: UK MSN Chap 10 §10.4.2.1 and §10.4.3.2 (oil fuel units precautions), A.1023(26) ch-4 §4.4.4 and International Carib Code chap 2 §2.21.4 (feedwater quality control), 2009 MODU Code cha-4 §4.4.4