User:Pbsouthwood/Navigational hazard

A navigational hazard or hazard to navigation is:

"Hazard to navigation means an obstruction, usually sunken, that presents sufficient danger to navigation so as to require expeditious, affirmative action such as marking, removal, or redefinition of a designated waterway to provide for navigational safety."

"navigational hazard Definition: Any obstacle encountered by a vessel in route posing risk or danger to the vessel, its contents or the environment."

"Hazard to navigation: An obstruction determined to have a substantial adverse effect on the safety and efficient utilization of the navigable airspace."

Types
Maritime hazards to navigation and airspace hazards to navigation.

Hazards to marine navigation
Hazards may be permanent, or temporary, including seasonal, and fixed or mobile, The risk associated with a hazard is aggravated when the position is uncertain, or the hazard is unmarked or obscured by poor visibility.,=
 * Fog is temporary, but may occur frequently in some areas and seasons
 * Icebergs are mobile and temporary, and also seasonal in some areas
 * Some river channels are variable
 * Some underwater obstructions are unidentified, others may be known.
 * Both wrecks with a fixed position and floating derelicts can be hazards
 * Seabed obstructions
 * Mined international waterways

Consequences

 * Marine accidents can occur, which can cause loss of life and vessels, or delays of shipping, unreliable transport of people and goods, and environmental damage.

Conditions determining a hazard
When deciding whether a static hazard will bw marked,the following factors may be considered:
 * Location of the obstruction relative to the navigable channel and relative to other hazards
 * Difficulty of navigation near the obstruction
 * Depth of water over the hazard, and how much it is likely to vary
 * Type of vessel traffic in the vicinity of the hazard, particularly draft, but also amount of traffic
 * Physical characteristics of the hazard
 * Probability that the hazard may move
 * Weather conditions that are likely in the vicinity
 * How long the hazard has existed in that location, and any history of accidents involving the hazard, and
 * Whether the object is considered a hazard in terms of alternative legislation

Navigational warnings
A navigational warning is information published or broadcast providing information on the status of one or more navigational hazards.