In ocean marine insurance, which risk involves delays or disruptions unrelated to accidents?

In the context of ocean marine insurance, the risk associated with delays or disruptions that are unrelated to accidents is best represented by strikes. Strikes can impact shipping operations significantly by halting labor at ports, which can lead to delays in loading and unloading cargo. This type of risk is often included in marine insurance policies because it is foreseeable and can have substantial financial repercussions for shipping companies.

While piracy involves theft and violence on the high seas, crew negligence pertains to human error that leads to operational failures, and the sinking of vessels is a catastrophic accident. These circumstances are related to direct operational risks or physical loss of property, rather than the broader category of delays caused by labor disputes. Hence, strikes are categorized as non-accidental disruptions, making them the correct choice in identifying risks that affect marine operations without involving an accident.