Collision Regulations, anchor lights,
and standard development
by Jo Neubert, FlexTek e.K.
1) Colreg requirements
Colregs define exactly which type of light is to be used when at anchor:
an all round white light is to be shown, if the vessel is less than 50m in length.
Colregs also define very clearly the range, colour and angular distribution of the light.
The range is given in Rule 22 "Visibility of lights",
and the corresponding physikal intensities and angular distribution in Annex I.
The following figures apply to anchor lights:
Range, all round white light, vessel less than 12m length: 2 miles
Minimum intensity for a range of 2 miles: 4.3 candelas
Horizontal sectoring:
- 5° above and below the horizontal: minimum intensity
- 7.5° above and below the horizontal: at least 60% of minimum intensity
These are essentially the requirements for motor boat lights,
but apply equally to sailing vessels not under way, i.e. at anchor.
2) Measurement data of the FlexTek Anchor Light
In our in-house laboraratory we got the following results for the light output:
The horizontal angular distribution was measured at the weakest LEDs.
The lines show the ouput of the two LEDs, plus the light halfway between the LEDs.
It would be rightly expected that there the minimum light output could be found.
After analysing the distribution it was concluded that the unit passed the requirements.
The Colregs also specify the colour of the light.
In our case, the left border of white with the CIE-coordinates
x=0.31,y=0.348 and x=0.31,y=0.283 is the closest to the LEDs in use.
With x=0.313 and y=0.307 we lie on the right, correct side of the CIE colour chart.
3) European standard developments
Of course, it would be nice to have harmonized navigation light standards throughout Europe.
To this end a new standard, (BS) EN14744 was agreed on and will come into force in every country in Europe.
One big exception are sports boats of less than 20m in length, which need comply with national requirements.
The biggest changes this new standard brings about are the harmonization of inland and offshore navigation
lights, as well as the acceptance of LED navigation lights.
Some additional requirements to Colregs are as follows:
- maximum vertical light variation is 1.5
- strain relief on hoistable lights for the cable of 50N (about 11 lbs)
- a means of indicating the user if minimum range of light has been reached
Whereas the FlexTek Anchor Light passes the first two requirements, the third one will require
additional electronics and make the new upcoming product in the future much more expensive.
In the meantime we advise users to change their FlexTek Anchor light after 10.000 hours of service.
What does this mean? The average user will display an anchor light say on about
50 nights per year, 8 hours long, giving 400hrs per year. Under these conditions the light should be changed
every 25 years to take account of the ageing of the LEDs.