Guidelines for Health and Safety on Board Small Fishing Boats

Smaller fishing vessels are put in danger when caught in extremely bad weather.

A large proportion of accidents involving small vessels are weather related. Bad weather makes the work environment onboard the vessel extremely hazardous. It also places a lot of strain on the vessel’s structure and equipment.

It is important to respect the weather at sea. Vessel operators should always know and understand what the weather is forecast to do.

Marine weather information.

Marine weather forecasts state what the weather is expected to do. This is done using series of measures as follows:

Wave height

Wave height used in forecasts refers to the waves that are generated by the wind in the area that is being reported. The measures used are:

Calm                    approx. wind wave height 0.1 m

Smooth                approx. wind wave height 0.5 m

Slight                   approx. wind wave height 1.0 m

Moderate             approx. wind wave height 2.0 m

Rough                 approx. wind wave height 3.0 m

Very Rough         approx. wind wave height 4.5 m

High                     approx. wind wave height 6.5 m

Very High             approx. wind wave height 8.5 m

Phenomenal       approx. wind wave height 11.0 m

Swell

Swell is also forecast. Swell comes from either a distant disturbance, such as a cyclone or depression or the swell develops from wind waves that have been blowing from the same direction for a length of time.

Swell height can be given in metres or named as follows:

Low                            Under 2.0 m

Moderate                 2 - 4 m

Heavy                        Over 4 m

Average Sea and Swell

The heights of both sea and swell refer to the average from the trough to the crest of the highest one third of waves present.

Occasional waves may reach much higher; about one in a hundred is likely to reach half as high again, and one in a thousand twice the quoted average.

Wind Speed
Wind Speed is given in knots and the direction given is where the wind comes from.

Warnings are issued as follows:

Wind     the wind is expected to exceed 33 knots (either steady or in gusts).

Gale       expect to about 45 knots as a steady wind, gusts can be 50% higher.

Storm     to about 60 knots as a steady wind, gusts can be 50% higher.

Tropical cyclone is over 60 knots but is only used for ‘hurricane’ type tropical storms.

Visibility Distance

Fog        Less than 1.0 nautical mile

Poor      1 - 3 nautical miles

Fair        3 - 6 nautical miles

Good     Over 6 nautical miles

Average visibility in New Zealand is about 15 nautical miles

Sources of weather information

The two easiest ways of getting a marine forecast are by VHF Radio and telephone.

VHF Radio

Marine weather forecasts are announced on Channel 16 at 0533, 0733, 1033, 1333, 1733 and 2133 hours.

Met Phone	Other sources of forecasts
	Local Coastguard stations on VHF Teletext. www.metservice.co.nz local newspapers (remember information can be relatively old) local radio stations National Radio at 0500 hours Auckland area has continual forecasts on Channels 20 or 21. Whitianga area has continual forecasts on Channel 23.