Hong Kong government departments conducted the annual marine pollution joint response exercises, Oilex 2026 and Maritime Hazardous and Noxious Substances (HNS) 2026, on the morning of October 22, 2026, in waters off Mo Tat Wan on Lamma Island, according to a government release issued that day. The drill tested responses to a simulated spill of oil and hazardous substances in Hong Kong waters.

In the scenario, an oil tanker collided with a container vessel, spilling fuel oil from the tanker, while five containers carrying Maleic anhydride fell overboard. An oil spill response team cleaned up oil on the sea surface, and the Fire Services Department and other groups were tasked with containing and handling probable spilled Maleic anhydride to protect nearby environment and facilities. Simulated actions included transferring fuel from the damaged tank and patching the leak, deploying floating barrier booms, spraying dispersant from pollution control vessels and a Government Flying Service helicopter, using oil skimmers, and a shoreline clean-up drill at the non-gazetted beach. For the HNS scenario, response groups lifted the damaged containers from the sea.

The Marine Department and Environmental Protection Department co-ordinated the exercises. Participants included the Fire Services Department, Government Flying Service, Hong Kong Police Force, Government Laboratory and Civil Aid Service, as well as several oil companies and a pollution control company they jointly formed. Organisers said the drills provided hands-on experience and helped parties adopt emergency strategies based on the properties and extent of spilled substances.