Lucas has seen a rise in the number of questions related to regulations for amber bulbs and has published its official advice for garages.
Today, amber bulbs are made with clear glass dipped in an amber coating.
Early ventures into this technique resulted in a cracked coating which caused a white light from the bulb – many will remember the amount of Rover 25s showing white indicators a while ago.
Since then, amber dipped bulbs have improved greatly and cracking is not such an issue any longer.
However due to the nature of the dipping process, Lucas say we are now seeing a wider variation in the shades of orange.
In a statement, Lucas said: “We have seen a small increase in concern surrounding the colour of replacement aftermarket bulbs in general.
“In response we have now committed to using the same lacquer as used in original equipment bulbs for all Lucas LLB581 amber bulbs.
“This will ensure that the chromaticity of the bulbs remain within the required coordinates but now reach further into the deeper orange more similar to that of the original bulbs.”
Bulb colour
The MOT test manual states that “every direction indicator emits an amber light.”
ECE Regulation No. 48 states that the chromaticity of amber bulbs must fall within agreed co-ordinates as follows:
It says: “Amber means the chromaticity coordinates (x,y)4 of the light emitted that lie inside the chromaticity areas defined by the boundaries.
“Limit towards green y ≤ x – 0.120, limit towards red y ≥ 0.390, limit towards white y ≥ 0.790 – 0.670 x.”
Meeting the regulations
Outside of the lab and without cutting edge test equipment it is impossible to tell the exact chromaticity of a bulb.
However, Lucas has said: “What we can say is, rest assured, all Lucas bulbs are batch tested throughout the manufacturing process and at our in-house test facility in the UK.
“This ensures that the required regulations are met and that our customers receive the consistent high quality expected from the trusted Lucas brand.”
To find out more about Lucas and to view its range of automotive bulbs, select ‘more details’ below.
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