A selective laser melting machine contains a couple of risk that need to be mitigated so the machine can be used safely.
The first risk is the laser radiation, with 33 watts of power this can cause serious injury if left unchecked.
The second is the fire/explosion risk, metal powder, oxygen and airflow create an enviroment that could explode or catch fire.
To mitigate this risk the design is made in such a way that from an operators perspective it is possible to look directly at the melt pool, furthermore a protective lid is placed that shields the operator from the blue/uv light. The Lid is checked by a safety circuit and will disable the laser and air pump as soon as the lid is opened.
For the fire/explosion risk mitigation, 2 oxygen sensors are added that are continuesly checked by the safety system. The sensors are verified every time the system is powered on and will also disable the laser and air pump when the conditions are not OK.
The extra features of the safety system are: If the safety system is triggered the printer will pause automatically, furthermore the oxygen level is communicated to klipper so you can also see the current oxygen level in the machine.
All human safety items have been carefully calculated and documented so the machine will comply to the CE regulations.
