In a college lab environment, this scenario is very unlikely unless someone has been ignoring the safety rules.
If possible, switch off the supply without touching the victim.
Disconnect the victim without making electrical contact. For example pull on dry clothing or use a non-conducting lever.
Call and / or phone for help.
Electric shocks are rarely fatal if the victim is resuscitated quickly.
Learn resuscitation techniques at a first aid class.
Risk Assessments
Before carrying out tasks, do a risk assessment.
THINK: Are there any dangers?
WORK SPACE: Look for common every-day risks like tripping over bags or cables or slipping on a wet or uneven surface.
TOOLS: Are there any risks involving tools like cutters or soldering irons?
VOLTAGES: Are there any electrical risks like high voltages?
CURRENTS: Are there any electrical risks like high currents that might make the circuit hot?
HEAT: Are there any risks involving heat or burns?
POLARITY: Are there any components that might fail if incorrectly connected? Electrolytic capacitors can be risky!
Common Risks
Trip hazards
Bags in the isles
Trailing cables
Chair, stool and furniture barricades
Clutter
Using Tools
Take care with wire cutters and try not to shoot shrapnel across the room.
Screw drivers and other sharp tools should point away from you so you are not hurt if they slip.
Cutting tools like knives, chisels and saws are particularly dangerous. Use then in such a way that you don't cut yourself.
Circuit Building
Get your circuits checked by the teacher before switch-on.
Beware of overheating components. There is a small burn risk.
Handle components carefully. Some have pointy pins that can stick into you.
Remove integrated circuits by careful levering with a small screw driver. This prevents the chip becoming plugged into your finger.
Handle wire cutters, pliers and hand tools with care. Keep the sharp end away from your fingers because there is a risk of minor cuts if you are not careful.
Fire Procedures
As soon as you hear the fire alarm, leave the laboratory at once. Do not delay to pick up books, coats etc.
Go to the designated assembly points well away from the buildings.
The location of the nearest fire alarm box is in the corridor about ten metres towards the nearest exit.
Laboratory Safety Rules
No eating or drinking in the laboratory - Toxic chemicals may have been used in the area.
Maintain orderly movement around the laboratory and access corridors at all times.
Chemicals and glassware may be being carried in these areas.
Keep walkways clear (of bags, coats etc.).
Keep liquids well away from equipment connected to mains electricity.
Safety goggles must always be worn when handling harmful chemicals, using a Bunsen burner or working with wires under tension.
Report any accident or breakage to the teacher immediately.
If in doubt about any verbal or written instruction, ask before carrying it out.
Electrical Safety
Don't overload power points by plugging in a Christmas tree full of adapters.
No trailing cables.
Check cables for insulation faults or exposed wire.
Don't mix water or liquids with electricity.
Always use correct plugs and sockets (no bare wires).
Remove metallic jewellery from your hands, wrists, neck etc.
There is an electric shock hazard if jewellery touches live equipment.
Don't wear personal audio devices. There is a time delay if you can't quickly hear a warning or call for help.
Always unplug the power cord before removing or re-installing any electrical component or circuit board, or when performing maintenance on electrical equipment.
Do not touch any exposed circuit with the power applied. (This does not apply to low voltage circuits - 12 Volts.)
Only connect the power when necessary such as when taking voltage measurements or waveforms.
Use one hand only. For example, do not insert probes with both hands. Keeping one hand behind your back or under the test bench will reduce the chance of fatal electrocution. This is referred to as the "one hand rule".
Do not leave any object loose on the equipment, such as screws, nuts or washers.
They can fall into the equipment.
This can cause failure at the time or later.
Ground / earth yourself properly before handling or replacing integrated circuits, processors, expansion, cards or RAM. Do this by touching the outside metal casing of the equipment and, if possible, use an anti-static wrist strap that is connected to the chassis/case/earth/ground.
Make sure that the equipment is grounded prior to removing its case. This minimises the chance of Electrostatic Damage. (ESD).
Get instructor approval before working on equipment.
Have the appropriate documentation before troubleshooting electronic equipment.
Always maintain a clean and safe work area.
Don't rush your work as this increases the risk of problems.
Be certain about what you are going to do. If you are unsure about a procedure, ask for help.
IF IN DOUBT, DON'T TOUCH/DO IT - ASK FOR HELP.
Know where the fire extinguisher is.
Know the fire evacuation procedure.
Know how/where to get first aid.
Know the location of first aid kits.
Know the emergency phone number
Portable Appliance Testing
Electrical and electronic devices used commercially or in schools or hospitals should be checked about once per year.
A portable appliance tester is used.
The devices are labelled to show they have passed the test.
This checks the mains wiring for correct earthing which is important for safety and also for leaking insulation caused by damp or aging cables.
At home, mains wiring should be checked for visible faulty insulation or wires pulling out of their plugs.