At night, moonlight and starlight have a light colour temperature of around 4000 Kelvin. Countless animals use the natural light from these celestial bodies to orientate themselves. Artificial light with the same light colour temperature makes this orientation harder, or even impossible, since the animals are unable to tell the different sources of light apart.

The new, lower light colour temperature of 3000 Kelvin will provide less competition with the natural light in the night’s sky, and therefore help to support biodiversity.

Yes. Of our roughly 750 stations, we have been lighting the following three stations using 3000 Kelvin light for several years:

• Bern, Welle 7 area: platforms 3/4, 5/6 and 7/8, since 2005.
• Zürich HB, Löwenstrasse through station: platforms 31/32 and 33/34, since 2013 (this exception of using 3000 Kelvin underground is due to a project-specific colour scheme and architectural design that also includes the light colour temperature).
• Oberrieden, platforms 1 and 2, since 2014.

As yet, no incident has occurred, nor have there been any negative reports on the lighting from customers or staff.

Yes. An analysis of accident statistics showed that lower light colour temperatures have no negative effects on the number of accidents.

The use of a light colour temperature of 4000 Kelvin in pedestrian underpasses is based on the results of tests of warm, neutral and cold white light from around 20 years ago.

The results then showed that neutral white light with 4000 Kelvin achieved the highest customer satisfaction and lowest level of pollution. With the use of neutral white light in above-ground areas as well, up until now there has been homogeneous lighting across the whole station.

The decision to light above-ground areas with warm white light means we are losing this homogeneity. The effect of warm white light on customer satisfaction and pollution levels today will determine whether underground areas will be also be lit with 3000 Kelvin in future. We are carrying out tests to evaluate this.

No.

We invited customers to station inspections. In particular, we wanted to consider the needs of people with disabilities and age-related health concerns (emphasis on people with visual impairments, deafness and the elderly). 

Warm white light with 3000 Kelvin received the greatest approval. The three most common comments were:

• Less blinding.
• Less industrial.
• Better contrast ratio.

All above-ground, covered and non-covered rail access areas.

Underground areas such as pedestrian underpasses and the track area will continue to be lit with 4000 Kelvin.

Yes, if the high-mast lights light rail access areas.

For the track area, please scroll down to the relevant section.

Yes, their availability is guaranteed by the replacement parts contract, meaning individual lights can be replaced 1:1 in the event of maintenance (A2) and fault repairs (A4). 

That means: for A2 and A4, individual 4000 Kelvin lights are to be replaced by individual 4000 Kelvin lights.

No. Lighting with planning approval for 4000 Kelvin may be implemented with 3000 Kelvin without a new planning approval procedure, as the change is in line with the requirements of the FOEN, and therefore also with the FOT.

Yes, they can be ordered via LeanCatalog (Ariba Guided Buying).

No. The lights have different SAP numbers.

Any erroneous orders will not be corrected since individual lights will have to be able to be replaced 1:1 for maintenance (A2) and fault repairs (A4). That means that for A2 and A4, individual 4000 Kelvin lights will be replaced by individual 4000 Kelvin lights.

The delivery period for new luminaires is 12 weeks.

Yes, and they can be ordered via LeanCatalog (Ariba Guided Buying).

Yes, this has no negative impact on operations or safety.

For a harmonious overall appearance, define zones (areas) that are lit entirely with either 3000 Kelvin or 4000 Kelvin.

Individual lights are to be replaced 1:1. That means 4000 Kelvin lights are to be replaced by 4000 Kelvin lights. Their availability is guaranteed by the replacement parts contract.

Yes, they are recorded as articles in Maximo in their respective standard classifications.

Ideally, this information

• will be visible in the inventory, if available via GIA code.
• will be listed in the operating point documentation.

The information can be found on a light:

on the serial plate.

The information can be found on an illuminant:

possibly printed on the old illuminant. The information can be deciphered as follows: 830 = 3000 Kelvin, 840 = 4000 Kelvin.

Light colour temperature can be determined clearly and correctly beyond any doubt using a measuring device. When evaluating which device is appropriate, please note that the value must not (only) be shown in coordinates, but directly in Kelvin (recommended measuring device: Gossen Mavospec Lite and Mavospec Base, prices: approx. CHF 2000).

For a complete renewal of a lighting installation, the new guidelines on light colour temperature in rail access areas apply. Planning approval is not required to switch from 4000 Kelvin to 3000 Kelvin since this change is in line with FOEN requirements, and therefore also with the FOT.

No, the change only affects the rail access area (including high-mast lighting). 

In the track area, tests will take place in all language regions (Zurich, Lausanne, Lugano) from January 2022 to September 2023 to clarify all important questions and issues. Staff working in the track area will be involved in this process.

Yes, although this luminaire is not for the track area; this area will continue to be illuminated with 4000 Kelvin. 

The luminaire with 3000 Kelvin is for the rail access area; it will be used there for high-mast lighting.

The delivery period for new luminaires is 12 weeks.

Yes, and they can be ordered via LeanCatalog (Ariba Guided Buying).

Yes, they are recorded as articles in Maximo in their respective standard classifications.