Well, it seems that you do not know much about photocopier, as a matter of fact, it indeed gives out a lot of radiation that could affect your health, but we usually do not use them 24/7 right? I mean, proper use of those photocopiers is just ok with your health and it is not serious enough to make you blind. But you should never ignore its harm, which means that you gotta avoid focusing on some of the laser device inside.
Yes, although we may say that we don't need to see like that in front of the computers, the photocopier will emit large amount of radiation which could be the several times than that of the computers or tv. That is the main reason to cause your blindness which will unconsciously break your eyes nerves and eyes cells. You'd better not do this often.
The working action principle of printer is to adopt the light guide of toner cartridges. Usually, it is very safe and will not damage the health of human body in normal working process. However, it has a little dazzling like the sun, if you stare it for a long time, it may burn your eyes in certain degree. The one which will hurt your health of printer is the dust that induced in the working process. The ozone and oxynitride will be the bad byproducts of working printer. We would better install exhaust fan and duct in the printing house. The one who has disease of respiratory system and pregnant woman will be not the right person to deal this machine.