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The Museum
of Road Signs and Signals
and street lighting
Traffic lights
Definition:
Illuminated signage is made up of all the luminous devices whose purpose is to regulate road traffic.
At MuSé, this department is structured around four main themes:
Traffic lights
Traffic lights
-Definition:
The purpose of a traffic light is to regulate traffic flows and it concerns all users of the public highway: cars, lorries, cycles, pedestrians, horse riders, etc.
They are also known as "traffic lights" or, more popularly, "red lights". These names are somewhat simplistic, since the traffic light is not necessarily tricoloured and, fortunately, is not always in the red phase. In professional circles, it's the "tricolour light signal SLT" that we hear about.
-Its history:
Let's go back to December 1868 in Westminster (England) to discover what are probably the beginnings of traffic light signalling. It was in Westminster that the first traffic control system was tested, probably as part of railway management. Rail traffic was managed using two coloured discs: one green and one red. In the early days, road traffic control also used just these two colours. The first system to be deployed in England used these two colours, which were themselves illuminated by a gas-operated device, all operated (by successive swivelling) by a policeman. Unfortunately, after an accident that cost the life of the policeman assigned to the signal, the idea was abandoned... until 1926 in Europe.
In the United States, the first electric light signal was produced in Cleveland in 1914. The system reappeared on the streets of London in 1926. In 1923, a traffic light was introduced in France. In its early days, the light signal had two colours, as mentioned above, whereas in France it only consisted of a red lamp that lit up.
-The light signal and its colours:
It's not enough to talk about the colours of the signal: we also need to talk about the position of the colours on the lantern.
-The position of the colours on the lantern:
Each colour is separated from the others and has a place on the lantern that is not random. It was at the first International Convention on the Unification of Road Signs and Signals in Geneva in March 1931 that the first rules on illuminated signs were laid down: red is placed above green. While this is of little importance to the average road user, it is of particular interest to people who are colour blind. Colour blindness is a disorder of colour perception linked to a deficiency of the retina and cones. For colour-blind people, it's not the colours that attract their attention, but the position of the lit lens: if it's lower, you're allowed to pass; if it's higher, you're obliged to stop.
Green:
Green is not the colour that human beings see best physiologically, it is the colour that they see the most and it is associated with the absence of danger.
Red:
Red is a very sharp colour that is biologically the best perceived by the human eye. It is also the colour that can still be identified in the dark. It has been chosen to identify danger.
What about orange?
Orange did not exist in the first lighting systems. This colour is intermediate between red and green and warns users when the signal changes from one colour to the other. The idea was first mooted in Geneva in 1931, but it would be decades before it was put into practice in Belgium. Orange was to replace the bell announcing the change of signal colour (green to red).
-Making the light signal visible:
In the past, the light signal has been made clearly visible to road users by various means:
-The "fire boxes" or "lanterns" were placed on a distinctive mast painted red and white. Each coloured line measured 15 cm.
-Each light box was black to increase contrast (the opposition of two things, one of which makes the other stand out).
-Each lens was fitted with a sun cap.
-The light box was surrounded by a contrast plate with a white border.
To increase the intensity of the light emitted by the lit bulb, the lamp was placed horizontally in the centre of a shiny aluminium reflector. As we shall see later, the coloured lens also played an important role.
-The MuSé's traffic lights through the ages:
The MuSé has the privilege of possessing signals that characterise the different periods in the evolution of the material:
The first light signals were two-coloured, and some were also painted black and white. There were no specific signals for pedestrians. When pedestrians were taken into consideration, a classic signal was dedicated to them. Liège knew these signals, some of which were still in place on Place Saint Lambert in the late 60s and early 70s.
Seraing 1956
Brussels 1935
It worked in a particular way: either there was a buzzer to announce the switch from green to red, or both colours were lit simultaneously when the switch was made.
In the 1960s, the three-lens lighting system gradually appeared across the country. Pedestrians were given special signals. In the 1961 Highway Code, it is written that the amber of the three-lens system has the same meaning as the red and green lit simultaneously in the two-colour system. Here are some common signals from the early 60s: the Westinghouses equipped with filament lamps, smooth, all-metal lenses (including the contrast plate), with a very special pedestrian signal.
In 1966, Westinghouse was taken over by Mécatherm, a Belgian company that manufactured boilers. The pedestrian signals took the form we know today. Here is a Mécatherm set, all these lanterns are fitted with 220 volt filament lamps. Note a modification to the lenses: they take on a more embossed appearance than previously, which improves the diffusion of light.
In the 1970s, ATEA (Antwerp) signals with three lenses became commonplace on the streets of Liège. The red signal here has smooth lenses, the others have raised lenses. They are equipped with 220 volt filament bulbs. Here, the contrast plate is made of polyester and the sun caps were originally made of metal before becoming plastic (PVC).
Liège 1976
Another lantern manufacturer appeared in the 1970s. These signals were made entirely of plastic, the lamps were filament lamps and they operated on 220 volts. The design of this equipment featured more enveloping sun caps, for example (Futurit, Swarco). The aperture of each lens is also different.
Liège, 1970s
In the 90s, halogen made its appearance in signage lighting. Each colour had its own transformer that lowered the voltage to around 10 volts. This technology enabled road managers to make energy savings, among other things. Here is a Futurit Swarco (Austria) device on the left and a Sagem (France) device on the right. The latter was very fragile in terms of the opening system and the sunshields.
Finally, since around 2010, all signals have been replaced by LED technology. Here are two signals from the Austrian company Swarco: on the left Alustar (42 volts) and on the right Futurit (220 volts).
-Other MuSé signals:
The first traffic lights reserved for public transport appeared in Liège in the 1980s. They were characterised by the absence of colours in the lenses, replaced by specific symbols: inverted triangle (green), circle (orange), bar (red). This is an ATEA lantern, with 220 volt filament bulbs.
Very nice combined signal, Swarco Futurit with 220 volt filament bulbs.
This unit comes from Beersel and arrived in November 2021. We have no information about this equipment, nor about the curious pedestrian signal.
-Old programme:
The 1975 Highway Code introduced a new traffic light: a flashing orange instead of the traditional green. In Belgium, this new configuration was to replace the programme illustrated here. Nevertheless, this old version was tolerated until 1 January 1980.
ATEA signal
-The "ghost" effect:
The "ghost" effect was described in the past mainly with light signals that had reflectors in the light box (filament lamps) and in sunny weather. The sun's rays would enter the lantern through the lens in the opposite direction, giving the impression that the signal was on. Accidents were reportedly caused by this "ghost" effect on the green lens. The signal below gives the impression of being in red phase when it is not even connected to its power supply. It is fitted with reflectors and 220 volt filament lamps.
The phantom effect does not seem to be described with signals equipped with LEDs.
-The caps:
Since the beginning of the use of traffic light signals, it has been possible to supply power to the lanterns via the top of the mast.
In this example, the three power supplies needed to operate the traffic signal for vehicles, the pedestrian signal and the "left turn" signal are distributed from the top of the mast (white circle).
This technical feature means that we have to take into account the possibility of water entering through the top of the signal. However, all the electrical contacts are located in the base of the pole, and it is imperative that they remain dry. So manufacturers came up with the idea of fitting the signal with a top cover to protect the electrical equipment. Over the years, these covers have come in a variety of shapes and materials:
This headdress was found in Charleroi. It probably dates from the 1930s to the 1950s. It is made of cast iron and weighs 3.2 kilos. It was "simply" placed on the signal mast. The MuSé renovated it with new white paint. In the photo on the right, this same cap was kept in place until the 1980s (Liège).
This example of the headdress presented by MuSé dates from 1963 and comes from the Chênée bridge crossroads, which was completely modernised in August 2015. It is made of aluminium and weighs 590g. It was screwed onto a bracket on the signal mast. The illustrative photo comes from Brussels and is a Westinghouse signal.
PVC cap, the latest to arrive on the market at the end of the 70s. It is considerably lighter, weighing in at 84 g. It was also screwed into the top of the signal. This was the trademark of ATEA signals. Over the years, the PVC deteriorated and the cap sometimes disappeared.
-Signalling and regionalisation in Belgium:
Since 1989, the country's three regions have been autonomous when it comes to road management. As a result, the policy of installing and maintaining traffic lights has become a regional responsibility...
Before regionalisation, under the aegis of the Ministry of Public Works, the whole country was equipped with traffic lights of the same appearance:
Mast with red and white stripes.
Black light box with white contrast plate.
The Walloon region:
The signals remained in the well-known configuration of unitary Belgium: red and white. The lanterns remained unchanged. It was only around 2010, with the arrival of LEDs, that the situation changed. While some crossroads were still equipped with red and white masts, the landscape gradually migrated towards more massive grey poles and lanterns without contrast plates, sometimes even without sun caps (Swarco devices).
The Flemish region:
In Flanders, the Minister of Public Works decided in 1990 to repaint all the country's illuminated signs in yellow and black. Officially, the reason given was better contrast, and therefore better visibility of the signs (even though these colours are also those of the region). So the landscape changed rapidly, and all the signs were repainted. It is sometimes still possible to come across "forgotten" signs or signs whose new paintwork is a little worn and gives a glimpse of the old configuration. Flanders quickly switched to LED (Swarco Futurit) and many crossroads are no longer equipped with contrast plates. Where these still exist, the edge of the plate has changed from white to yellow.
The Brussels-Capital Region:
In October 2013, the then Minister for Mobility decided to repaint the region's traffic lights in... blue and yellow this time. Here, we don't know the official reason, as the notion of contrast probably didn't prevail. Let's not forget that blue and yellow are the colours of the Brussels-Capital Region. The idea was quickly abandoned as it would have meant repainting 4,500 poles at a cost estimated at the time at 1 million euros. Faced with an outcry over this not really essential expense, the idea was abandoned. A trial was nevertheless carried out at the junction of rue Belliard and the "petite ceinture" in Brussels.
Crossroads between Rue Belliard and "petite ceinture" R20 (Avenue des Arts), Brussels:
Here is the result of this painting work in 2013. The masts remained like this until at least 2017, when they were fitted with LED lanterns. Subsequently, the entire crossroads was re-equipped with Swarco signals with grey masts. This is the equipment that was chosen by the Region in 2010 to modernise all the traffic lights.
(Source: Feu routier.free.fr)
-Special features:
While the configuration of traffic light signals was largely uniform before regionalisation, this is no longer the case today... even between regions of the country! What's more, depending on local circumstances and budgetary constraints, the equipment may have to be completely replaced or new lanterns installed on old masts.
New lantern from the Swarco Led range installed on an old red and white pole. We are in Brussels.
Recent installation (after 2000) using Swarco LED lanterns on red and white poles. Photo taken in Beyne-Heusay (Liège).
Traffic lights at the crossroads between the N636, 983 and 97 in Havelange. The entire site was equipped with ATEA lanterns, which were still in place in 2009. All these lanterns have been replaced by Swarco equipment, but the masts have been retained.
-The coloured lenses of light signals:
Nowadays (since 2010), signal lights are equipped with LED technology. The colour of the signal is obtained both by the LED itself and by the coloured lens. Some signals no longer have coloured lenses, while others still do. These lenses are made of plastic. This material appeared towards the end of the 70s, at the same time as the appearance of light boxes, also made of plastic.
The first generations of lenses were made of coloured glass. ATEA, Westinghouse, and later Mecatherm, equipped their signals with these glass lenses (filament bulbs). However, Mecatherm also manufactured signals with plastic lenses... ATEA and Westinghouse have always used glass. The structure of moulded glass came in various forms:
Smooth glass:
It was not completely smooth, but the lens presented a surface without any clear relief. The light was then distributed over the lens thanks to the aluminium reflector:
Curved glass:
The lens featured curved vertical lines. This allowed the light to be distributed more evenly over the lens, making it easier to see:
"Spider web" glass:
The "spider's web" moulding of the glass was adopted by all signal light manufacturers: ATEA, Westinghouse, Mécatherm, Swarco Futurit. This aspect of the lens enabled the light rays to be distributed over the entire lens, making it more visible to users:
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