Safety Instructions for ECE Power Laboratories
Purpose of the Safety Handout
- The purpose of this document is to ensure the safe and smooth execution of experiments in ECE laboratories. The safety rules have to be followed at all times when you are present in the laboratories.
- You have to carry out the experiments in such a way that nobody will be injured or hurt and the equipment will not be damaged or destroyed.
- Every student who participates in the lab course has to sign the safety agreement at the end of this document.
General Lab Rules
- Absolutely no food or drinks of any kind are allowed in the labs.
- Read the handout and procedures before starting the experiments and follow all written and verbal instructions carefully. If you do not understand the instructions, the handouts or the procedures, ask the instructor.
- No horseplay or practical jokes involving lab equipment or procedures. Intentional misconduct will lead to the exclusion from the lab.
- Keep the workplace tidy before, during and after the experiments.
- Immediately report dangerous or exceptional conditions to the instructor. Report also any problems with the lab equipment (not working as expected, wires or connectors are broken, the equipment that smells or "smokes")
- After the lab session, disconnect all cables between your circuit and the bench instruments and switch off their power.
The direct impact of electrical current to the human body can cause serious injuries and even death. The damage depends on the amount of current, the kind of current (AC or DC), the frequency, and the way the current flows through the body. Up to about 0.5mA current flow in the body is imperceptible. Above this a slight tickle is noticeable. Over 10mA there will be muscle contractions in the part of the body, which is flown through by the current. The hands may not be able to release things. Also respiration problems take place. In case of good health this is still not hazardous. For higher currents up to 200mA the duration of the current flow is important. If the current is switched off early enough there is still no effect on health. Rising currents above 200mA causes fibrillation and cardiac arrest. At currents above 500mA the body is also poisoned by chemical effects, which also can cause death even after some days.
In general, DC current is less dangerous but also shows all the described effects at higher
values. There is no absolute value of safe voltage definable, because the resistance of the
human body differs between 600 and about 6000 Ohm. It is dependent upon the wetness
of the skin, the individual person and the voltage. With higher voltage the resistance
lowers! Generally, voltages above 50V can be harmful. Note that experiments in the
power laboratories use voltages well in excess of these values but they can be conducted
safely if safety procedures are followed at all times.
- No power laboratory experiment should be performed without an instructor present.
- Avoid bulky, loose or trailing clothes. Remove metal bracelets or watchstraps. Avoid wet hands and clothing.
- Before starting experiments familiarize yourself with the equipment layout, including electrical connection and mechanical components. Know the location of the Emergency Power Off button.
- Before power is turned on: (1) circuit connections and layout should be checked by an instructor, unless specifically advised otherwise, and (2) all colleagues in your group should give their assent.
- Never make any changes to circuits or mechanical layout without first switching off the power.
In Case of Emergency
- Keep cool.
- Warn persons at risk, punch the emergency shutdown.
- Immediately notify the instructor or call 3111.
- Try to help, but take care of yourself
When someone suffers serious electrical shock, he or she may be knocked unconscious. If the victim is still in contact with the electrical current, immediately turn off the electrical power source or push the Emergency Power Off button.
Do not touch a victim that is still in contact with a power source; you could electrocute yourself.If you call emergency services they need the following information:
Have someone call for emergency medical assistance immediately. Administer first-aid, as appropriate.
- Where did it happen?.
- What happened?.
- How many people are involved?.
- What kind of injuries/ diseases?.
- Wait for further questions! Don't break off the call yourself.
Safety Instructions for the ECE Laboratories – Agreement
I have read and agree to follow all of the safety rules. I realize that I must obey these rules to insure my own safety, and that of my fellow students, instructors and teaching assistants. I will cooperate to the fullest extent with my instructor and fellow students to maintain a safe lab environment. I will also closely follow the oral and written instructions provided by the instructor. I am aware that any violation of these rules that result in unsafe conduct in the laboratory or misbehavior on my part, may result in being removed from the laboratory, receiving a failing grade, and/or dismissal from the course.