This Act provides rules for access to and navigation of Thai waters as defined in section 3. It also, to a certain extent, concerns protection against pollution of marine and inland waters. the Act also requires a power-driven vessel which is a Thai seagoing and of sixty gross tonnage or more and any foreign ship to report to the harbour master when entering a port or when leaving Thai waters. There are specific rules for the Bangkok port area. Fishing in rivers or ports that obstruct navigation is prohibited in the Bangkok port area and requires a permission in other navigation areas.