What do visible white green and red lights indicate?

Vessels underway at night must show navigation lights between sunset and sunrise. Navigation lights indicate:

• presence of a vessel
• approximate direction of travel
• type of the vessel ie - power-driven or sailing.

Recent changes to the Inland Navigation Rules make them nearly identical to the International Rules, so we will describe the International Rules to simplify the choices.

Basic rules:

• Side lights are red (port) and green (starboard) and shine from dead ahead to 112.5° aft on either side.
• Stern lights are white and shine aft and 67.5° forward on each side. (Thus, the side lights and stern light create a full circle of light.)
• All-round lights are white and shine through 360°.
• Masthead lights are white and shine from 112.5° on the port side through dead ahead to 112.5° on the starboard side. They must be above the side lights.
• Sailboats under power are considered powerboats.
• Side lights may be combined into a single "bicolor" light.
• Powerboats less than 20m (65.5') in length need to show side lights, a stern light and a masthead light. Power vessels less than 12m may show a single all-round light in lieu of the separate masthead and stern lights.
• Sailing vessels less than 20m in length need to show side lights and a stern light. These may be combined into a bicolor light and stern light, or a single tricolor light at the top of the mast. Sailing vessels under 7m must have an electric torch or lantern available for collision avoidance.
• When anchored outside a special anchorage, power and sail vessels under 20m must display an all-round light. Vessels under 7m are exempt, unless anchored in a narrow channel or anchorage, or where other vessels usually navigate.

Small rowing and sailing boats are the only vessels that don't need navigation lights when operating at night, but operators of these vessels must instead carry a torch or lantern showing a white light and show it in sufficient time to prevent a collision.

Vessels under 12 metres in length use the following lights in various combinations, depending on whether the vessel is sail or power-driven, underway or at anchor.

Power-driven vessels while underway must show either:

• a masthead light, separate or combined sidelights and a sternlight or
• a white light visible all round and separate or combined sidelights, provided that the all-round white light is positioned so as not to interfere with the operator's vision.

The masthead or all-round white light must be a minimum of one metre above the sidelights.

Lights required for power vessel underway

Sailing vessels while underway must show:

• separate or combined sidelights and a sternlight or
• a single, tri-colour lantern, fixed to the masthead.

Lights required for non-power vessel underway

Vessels at anchor, either sail or power-driven, must show a single white light visible all round.

Lights required for vessels at anchor

Vessels undertaking dredging, diving or underwater operations display either two black diamonds in daylight hours or two green lights at night to indicate the side on which it is safe for other vessels to pass.

This is the only time when red and green lights may not indicate a vessel's direction of travel.

A dredge also displays either two black balls in daylight hours or two red lights at night on the side where dredging is taking place - to indicate where it's unsafe to pass.

These guidelines have been developed for power boats less than 20 metres in length and can help you:

• select the right lights for your boat
• avoid common problems when locating lights
• wire lights up correctly

Legal requirements

By law, navigation lights and their installation on recreational boats are required to comply with the positioning and technical requirements of an international agreement, commonly known as the International Regulations for Preventing Collisions at Sea (COLREGS).

Marine Safety Authorities enforce the requirements of the COLREGS and can provide a summary of those requirements as they apply in your local area.

General advice on installation

Avoiding damage

Navigation lights must be installed in accordance with the manufacturers' instructions. Navigation lights should be mounted so as to minimize damage by contact with other objects under normal operating conditions, for example, lights mounted on the topsides of smaller craft can be damaged when coming alongside a wharf or pontoon, and lights mounted at the bow near anchor fittings could also be vulnerable and need to be protected.

Lights affecting the operator's vision

Navigation lights must be installed to prevent the lights from shining into the operator's eyes. For open boats, this can be achieved by using a shielded light on a mast or pole. This could also be achieved by placing the light support behind the operator and above head height, rather than in the bow or amidships. Some LED lights are less prone to affecting night vision than conventional incandescent lights.

Wiring

Navigation light wiring must be installed in accordance with a recognised wiring code. A white cable is normally used from the switch to the light and black is used for the return or negative conductor. The circuit should be fitted with a fuse or circuit breaker and no other equipment, apart from navigation lights, should be on that circuit. Conductors used for wiring must be sized to ensure no more than a 3% voltage drop.

The lights should be wired so that one position of the switch turns on all the required running lights and a different position turns on just the anchor light. Alternatively, two switches that achieve this same result could be used.

Which light fittings to use

The Australian Maritime Safety Authority maintains a register of compliant safety equipment that includes navigation lights. If you choose to fit a light that isn't on the register, make sure that it meets the performance requirements of the COLREGS. Pay particular attention to the shielding arrangements to ensure the light only shines in the correct direction and there is no overlap on combination lights.

Points to note with specific types of lights

All round white light

An all-round white light shows over a nominal arc of the horizon of 360°. The light fitting must be located at least one metre above the sidelights; and should as far as practicable, be on the centreline of the boat. As a general rule, an all round white light should not be obscured by masts or other structures by more than 6° of arc. If that's not possible, or the light would shine into the operator's eyes, a masthead light in combination with a stern light is an alternative to an all round white light.

Masthead light

Boats over 12 metres in length are required to have a white masthead light, mounted at least 2.5 metres above the gunwale that shines forward over an arc of the horizon of 225°, so that it can be seen from ahead of the boat to just aft of the beam. In addition, regardless of the vessel's length, the masthead light must be located at least one metre above the sidelights; and should as far as practicable, be on the centreline of the boat.

Stern light

A stern light is located near the stern to show a white light over an arc of the horizon of 135° behind the boat. On an outboard craft, it may be necessary to mount the stern light on a mast, or to one side of the boat, to avoid the motor obscuring the light.

Side lights

Most boats need to have a port (red) and a starboard (green) side light each showing an unbroken light over an arc of the horizon of 112.5° from dead ahead to slightly after of the beam on either side. If the design of the boat allows, a combination port and starboard light unit can be mounted on the centreline of the boat, in place of two individual side lights.

Individual side lights come in two styles, those intended to be mounted on a horizontal surface such as a deck and those intended to be mounted on a vertical surface such as the topsides or the side of the cabin. Be careful not to mount lights on a horizontal surface if they are designed to be mounted on a vertical surface, and vice-versa, because they will shine in the wrong direction.

Horizontally mounted side lights generally come with a reference line marked on them which must be kept parallel to the centreline of the boat when fitting the light.

Vertically mounted side lights must be fitted with the back of the light parallel to the centre line of the vessel so that the light will be visible in the correct sector and the lights don't cross over. This means when lights are mounted on a vertical or near vertical surface that is not parallel to the centre line or not vertical, a wedge or similar must be provided to achieve the correct alignment in both planes.

Range of visibility of lights

Minimum visibility for length of vessel (nautical miles)

As with channel and other lateral markers, the green sidelight indicates starboard and red indicates port, when looking in the direction of travel.