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Frequently asked questions about chromium trioxide

Chromium trioxide has been detected in some of our trains. As a result, we have received a great deal of questions from current and former employees, as well as other concerned parties. Here you can read answers to the most frequently asked questions about chromium trioxide.


All questions and answers about chromium trioxide at NS

Q: Where has chromium trioxide been detected in the trains?
A: It is found in old layers of paint on the exterior of the following train types: SGM, ICM, ICR, Mat’64, loc DDAR, DDM1, E1700 and may be found in certain fasteners used in the trains.

Q: Should passengers be concerned?
A: No, passengers are not exposed to chromium trioxide. In its solid state in layers of paint, chromium trioxide is not harmful.

Q: Should employees be concerned at this point in time?
A: Assuming that employees use the correct protective equipment, there are currently no indications that they should be concerned. Work involving dust, such as sanding, should always be carried out while using appropriate protective equipment anyway. We will continue to remind our employees abide by the safety regulations. Safety regulations are also constantly monitored and updated as necessary. 

Q: Can NS engineers come into contact with chromium trioxide?
A: No, engineers do not come into contact with chromium trioxide. In its solid form in old layers of paint, chromium trioxide is not harmful.

Q: When was the chromium trioxide discovered?
A: In late May 2015, the paint on the train type DDM1 was tested as part of preparations for restoration work. In early June, the research results showed that chromium trioxide was present in the layers of paint on this type of train. Last year, we also investigated whether chromium trioxide was present in the paint that is used during overhauls and maintenance. This was not the case.

Q: In which workshop has work been done on layers of paint (sanding for example)?
A: The issue primarily involves the NS workshop run by NedTrain in Haarlem. But sanding was or is carried out in other workshops in Onnen, Maastricht, Leidschendam, Zaanstraat (Amsterdam), the Watergraafsmeer (Amsterdam) and the former workshop in Tilburg.  

Q: What kinds of activities may result in exposure to chromium trioxide?
A: Chromium trioxide can be released as dust when sanding or cutting or as smoke when welding. These activities are not just hazardous because of chromium trioxide, but also because of harmful welding smoke or the fine dust produced when sanding. These are well-known dangers in the industry and the current working conditions and safety regulations had already been adapted to deal with them. Now that we are aware that chromium trioxide is present in some trains, we have taken a closer look at our work activities. Research has shown that chromium trioxide is released as a result of the following activities:

  • Cleaning of trains with compresses air after sanding
  • Sanding when repairing the exterior wall
  • Cutting into the wall and hull plate behind the foot-board in the grit cabin
  • Sanding of the stainless steel wall
  • Moving trains by means of air cushion transport

Q: What are the risks?
A: Chromium trioxide in dust or vapour form poses increased health risks when a person is exposed to excessive amounts (above the legal norm) for a long period of time. By taking protective measures, such as limitation of the duration of activities or the use of personal protective equipment, exposure can be minimised and risks avoided. Upon investigation, it appears that our methods of working do not result in levels of exposure that exceed the permitted norm. However, NedTrain wants to limit exposure as much as possible. That is why we will be taking additional measures to optimise working conditions. For example, by using new dust covers and other methods.

Q: What is the safety situation at NedTrain?
A: At NedTrain, there is a safety culture within which employees are continuously and openly informed about hazards and potential hazards. This is done to make sure that the frequency of safety incidents continues to decline. Employees are asked to report incidents and are also actively informed of areas for improvement or situations which can be learned from. By continuously drawing lessons from incidents, NedTrain and NedTrain Haarlem have lower than average numbers of safety incidents and their frequency has been steadily decreasing for years. As is conventional in the industry, we measure this using the so-called LTIR. This score involves all physical, work-related accidents that cause more than 24 hours of absence. When expressed per million worked hours, the number of physical accidents gives NedTrain a Lost Time Injury Frequency Rate (LTI) of 6 in 2012, 3 in 2013 and 0.39 in 2014. The number of railway accidents has also been declining over the past few years (68 in 2012, 53 in 2013 and 40 in 2014).

Q: How many employees have been exposed to the substance, directly or indirectly?
A: We are unable to determine the exact number at this time. This is still being investigated. We have asked experts to validate our approach in order to exclude any uncertainties.

Q: Have any employees shown signs of having health problems?
A: Several employees have reported health problems. It is not yet clear whether these are related to chromium trioxide exposure. 

Q: Are employees concerned?
A: Discussions with employees and the works council have revealed that some employees are concerned for their health as a result of current and/or past working conditions. We have offered current and former employees a health-check and are keeping them informed of all measures.

Q: How have former employees been informed?
A: Based on information from the Spoorwegpensioenfonds, former employees were informed in writing in a letter sent to their home address. These letters were sent in the week of 10 October. This took some time because we were dealing with sensitive information that was subject to the relevant privacy legislation. Former employees can look up information on the NS website themselves http://www.ns.nl/overns/nieuwscentrum/dossiers/dossier-chroom-6.html and can contact CAOP if they have questions.

Q: Why did NS not reveal this information itself?
A: Because the risks appeared to be small, there was not initially a direct reason to do so. A choice was made to focus on those directly involved (employees, works council, trade unions and the iSZW). We have been communicating with these parties since the chromium trioxide was first detected.

Q: Has the extraction of chromium trioxide dust had an environmental impact?
A: No, no chromium trioxide dust has been released into the open air.

Q: When will the Mat’64 material type be removed from service?
A: Approximately 70 Mat’64 trains were removed from service in mid-December 2015.

Q: As an employee, who can I ask specific questions about work activities and the associated risks?
A: You can field these questions to your supervisor, ask them on the NedTrain Intranet or ask at the CAOP where a hotline has been set up to deal with any questions.