Supplementary panels: how they complete the meaning of road signs

The sign and panel form a single message

First identify the main sign, then add the information shown on the supplementary panel. A no-traffic sign with the hours 7.30–19.00 means that the prohibition applies during that period, not that entry is allowed then. Likewise, a rain symbol below a slippery-road warning links the danger to a wet road surface.

Information from several panels must be combined. A public-holiday symbol with a time range means that both conditions must be met. The word ‘except’ instead excludes the pictured category from the prohibition. Reconstruct the whole sentence before acting.

• Identify the meaning of the main sign
• Add all the conditions shown below it
• Apply the complete message to the actual situation

Distance and length: two different measurements

A distance panel shows the space between the sign and the announced point. A simple measurement such as ‘320 m’ below an uneven-road sign means that the uneven stretch begins 320 metres farther on. It does not describe the length of the uneven road.

A length panel shows how long the affected stretch is. It has a measurement flanked by two vertical arrows, one on each side. ‘380 m’ below a dangerous-bends sign means that the bends continue for 380 metres from the start of the stretch. Distance asks ‘how far until it starts?’; length asks ‘how long does it continue?’.

• Measurement without side arrows: how far it is to the beginning
• Measurement between two vertical arrows: length of the affected stretch
• The sign above explains what is being measured

When the sign applies

Time panels establish the period during which the main sign applies. ‘0–24’ means throughout the day, while ‘7.30–19.00’ indicates one continuous period between those times. If no symbol for a type of day is also shown, the time range applies every day. Outside those hours only the time-limited effect of that sign ends; all other rules of the road remain in force.

The cross represents public holidays, while the two crossed hammers represent working days. These symbols should not simply be read as ‘weekends’ and ‘Monday to Friday’: the calendar is what matters, and Saturday is normally a working day unless it is a public holiday. When a day symbol and a time range appear together, the sign applies only on the represented days and during the stated hours.

Who the sign applies to and who is excluded

A black symbol on a white background can restrict the sign to a particular category. If a lorry appears below a no-traffic sign, the prohibition concerns the vehicles represented by the panel; it does not become a general prohibition for everyone. To interpret it correctly, identify the pictured category and also take account of any mass information shown in the sign assembly.

When the symbol is preceded by the word ‘except’, the meaning is reversed: that category is excluded from the rule. A no-entry sign with ‘except buses’ therefore allows buses to enter while continuing to prohibit entry to the other road users concerned. The exception applies only to the sign with which it is grouped and does not remove speed limits, priority rules or other requirements on the road.

• Symbol alone: the rule applies to that category
• ‘Except’ plus a symbol: that category is excluded
• The exception does not cancel other rules

Where the rule begins, continues and ends

Beginning, continuation and end panels mark the position of a warning, rule or indication along the road. Their arrows do not instruct you to go straight ahead, turn or go back. They locate the sign within the affected stretch. There are versions with vertical arrows and versions with horizontal arrows.

In the vertical series, an upward arrow marks the beginning, two opposing arrows mark continuation and a downward arrow marks the end. In the horizontal series, the same order is represented by a left-pointing arrow, a double arrow and a right-pointing arrow. With a no-parking sign, for example, continuation confirms that the prohibition applies both before and after the sign's position.

• Beginning: the regulated stretch starts at the sign
• Continuation: the stretch continues before and after the sign
• End: the regulated stretch finishes at the sign

Symbols that explain a particular situation

Another family uses symbols or short words to make the main sign more precise. A paintbrush means that road markings are being renewed; colliding cars indicate an accident; locomotives refer to shunting tracks; and a blade with a snowflake announces a snowplough at work. Waves, a line of cars and a works vehicle respectively indicate an area liable to flooding, a queue and machinery moving on the road.

Other symbols explain the cause of a danger. Ice crystals or a rain cloud, when paired with a slippery-road warning, specify when loss of grip is more likely. A slow lorry on a slope instead warns that you may catch up with heavy vehicles travelling at low speed. In every case, the appropriate behaviour follows from the complete message: reduce speed, increase the following distance and prepare for the situation shown.

Removal, street cleaning, lanes and the priority road

A tow-away panel below a no-parking sign warns that a vehicle left in breach may be removed or, where the rules allow, immobilised. A mechanical street-cleaning panel instead adds the days, hours and sweeper symbol: during that period the stretch must remain clear so that the service can operate. Neither panel creates a prohibition on its own; each completes the sign placed above it.

A downward arrow identifies the lane to which the sign applies. ‘Hairpin bend’ or ‘3 hairpin bends’ announces one or more very tight bends. On a junction panel, the thicker line is the road retaining priority and the thinner lines are minor roads. The diagram shows the priority route, not necessarily the junction's actual proportions.

A simple method to avoid confusion

When faced with a group of signs, follow the same order every time. First identify what the main sign warns about, prohibits, requires or allows. Then classify each panel: distance, length, time, category, exception, position within a stretch, particular situation or course of the priority road. Finally check whether your vehicle, the day, the time, the lane and your position are covered by the conditions shown.

This method prevents the most common misunderstandings: confusing distance with length, reading an arrow as a mandatory direction, mistaking a restriction for an exception or overlooking the day symbol. On the road, signs must be read quickly but not carelessly. Once the complete group is understood, the driver can prepare for the danger or comply with the rule in good time.

• What does the main sign communicate?
• What information does each panel add?
• Does the actual situation fall within the complete message?