🔍 Key Concepts

• Spontaneous combustion usually involves slow oxidation of materials that generates heat over time • Difference between cargoes that ignite from an external source vs. materials that can self-heat and ignite • Housekeeping hazards on tankers, especially rags and waste contaminated with oil

💭 Think About

• Which option can heat up by itself over time without an external flame or spark, just from slow chemical reaction with air? • Which choices are normal flammable cargoes that typically require an ignition source, rather than catching fire on their own in storage? • On an exam, when they say "chief source" of spontaneous combustion, are they asking about a specific product, or a bad housekeeping condition that can exist on any tanker?

✅ Before You Answer

• Identify which choice involves waste material + absorbed oil rather than clean liquid cargo • Ask yourself which hazard is emphasized in tankship safety and housekeeping training as a leading cause of spontaneous ignition • Confirm that spontaneous combustion is about self-heating over time, not just being highly flammable when exposed to a spark or flame