Recently an article on Rapex came to our attention.

It concerns an industrial sheet metal laser processing machine.  On the surface the machine looks modern, clean, well designed and fully encapsulated.

However the importance of detail should never be overlooked. German market surveillance investigated the machine and discovered its protective windows only offer protection level of 0.02, instead of the required level of 4!

How they came to inspect this machine and specifically decided to test the protective windows we can only speculate. However it does make you wonder if some poor worker is now left with reduced vision as a result of this machine or hopefully just a close call!

How do you know your protective windows are correctly rated for your application?

In contrast to Personal Protection Equipment there is no requirement for 3rd party testing by a notified body, or a requirement for marking the protection windows with a rating.
The only option you have: short of testing the windows yourself, is to trust in the manufacturer. Trust that they are sourcing correctly rated protection windows.

How do you know you are working with a manufacturer you can trust?

Questions are your tools here. Aside all the other questions and points to check that we have covered on LaserMachineSafety.eu ask them what the windows are made of, what are their rating?
Manufacturers struggling to provide correct documents (DoC) or answers simple questions they should know often mean they don't want to answer or they don't know the answer. Neither inspire confidence or trust.