Let me give some Safety tips and will cover it under two headings - Personal Safety and Equipment Safety.
Disclaimer: The safety aspects that are discussed here are based on my experience and Please read the Manufacturers User Manual and adhere to them stricktly. My views given here are in addition to what is mentioned in respective user manuals and doesn't neccessarily replace what is conveyed there. Any incidental damages/death caused by following or not following the tips given here is purely at your risk and I can't be held responsible.
This is applicable for all people whether they use a Dishwasher or otherwise. Whether you reside in an apartment or individual house. Ensure that all your electrical lines are properly Earthed. You might have experienced as well, if you touch any appliance accidently and you feel a mild shock or feel like current is passing then this is the reason. Either the Earth wire is missing or not connected properly. The easiest and best way, as far as I'm aware, is, to engage an Electrician who works in the Industry who is certified and well versed in handling Heavy Current. The electrician employed by the builder or by your building contractor or a person from nearby Electrical shop cannot be relayed generally. I got in touch with a person who does contract work for Industrial and Corporate offices - Cost is marginally high but Safety is assured. If you are working in an MNC or Corporate company or in Core Industry, definitely you company is going to have a certified electrician.
Socket (Amperage) and Internal Electrical Wire
This is applicable for all people whether they use a Dishwasher or otherwise. Your Dishwasher would draw any where above 2000Watts and for such kind of heavy machine, you need to have atleast 16A socke/plug and supporting internal wires. Any inferior quality wires / socket / plugs would be a strict NO. Ensure that you are using Socket, Wires and Plugs from a branded company and wires especially should be of right gauge. An electician from Industrial background would be able to advice correctly.
Don't ever think of using an extension box. I can't say any further. If you ask me extenstion box should be banned. This along with poor quality wires and loose connections are major cause of accidents. Don't do it.
This is applicable for all people whether they use a Dishwasher or otherwise. Have an habit of performing this small check. You have operated an heavy duty machine like Washing Machine, Dishwasher, Microwave Oven, AC, etc, after you have switch off the appliance and the main socket, check if you feel any heat around those Socket / Plugs [ensure you are properly protected from any accidental shock]. If so it is time to call a Trained Electrician and ask him to inspect and replace neccessary Socket/Plug/Wire with a good quality material. Additionally check the wall / floor for any dampness and take rectification steps.
Running Dishwasher while you are away or asleep
We use to do this before and considering all the safety measures that I talked about, you could avoid this if you plan it well. Some times there are huge fluctuations happening during night (depending on the area you reside), I happen to notice one night that our fan was running on Inverter power inspite of Mains working, due to low voltage.
Opening the door when the Dishwasher is working or wet
This generally happens when you want a particular vessel which is being cleaned currently and you can't wait until the entire cycle gets completed.
(Please read Disclaimer again)
Ensure that you have switched off the Dishwasher completely. By completely, I mean, the on/off button in your dishwasher is in off position and that switch near the power plug on the wall is in off position, if you are extra cautious remove the plug from the socket. [Take neccessary care]. After you have ensured that there is no power supply going to your dishwasher and that Dishwasher has stopped operating, you can think of taking out the vessel. Remember that water or water vapour inside the dishwasher is going to be hot depending on, at what stage, you want to retrieve. So be careful while opening the door.
Proper Earthing, Socket and Internal Wiring are important as mentioned above. It is better to have a good voltage cut-off equipment to protect the Dishwasher from getting exposed to huge voltage fluctuations while it in operation. Su-Kam has a equipment, you could explore. IFB suggests a similar unit but I'm not quite happy with the product as it went bad just after a year.
Any good / standard product available in the market with proper Load specification should help. It is not absolutely necessary though. But what happens generally is, the controller board used inside the Dishwashers are imported from outside the country and hence they are generally not stocked in Franchise office but in the Regional Offices,so if it goes bad, you are going to see some delay in getting it replaced. Develop contact with your Branch Office service head, so that the delays are minimal.