Workplace Safety, ESD and Environmental Practices
This domain tests electrical safety, electrostatic discharge control and responsible disposal of electronic waste. It is a high-value area because unsafe habits cause injury, latent damage and legal problems.
Electrical and workshop safety
Isolate power before repair, use lockout/tagout where applicable, and verify with a tester. Wear appropriate PPE, keep liquids away from benches, and use the correct fire extinguisher: CO₂ or dry powder for electrical fires, never water. Know basic first aid for electric shock and burns. Keep a first-aid kit and fire blanket accessible.
ESD control
Static discharge can destroy or weaken semiconductors without immediate failure. Use a grounded wrist strap with a 1 MΩ series resistor, an anti-static mat, and grounded soldering irons. Store ICs in conductive foam or shielding bags. Avoid synthetic clothing and low humidity; handle boards by the edges.
Environmental practice
E-waste contains lead, mercury and cadmium. Separate batteries, CRTs and circuit boards; never burn cables or dump them in household waste. Follow RoHS restrictions on hazardous substances and prefer lead-free solder where specified. Recycle through authorised collectors.
Worked example
A technician feels a spark when touching a board. The likely cause is ungrounded static. The fix is a wrist strap connected through 1 MΩ to a verified earth point, plus an anti-static mat. The resistor limits current if the technician contacts live voltage.
Traps that cost marks
Wearing a wrist strap that is not grounded; assuming an anti-static bag protects a board while it is being handled; using water on an electrical fire; mixing batteries with general waste.
Exam focus
Match the hazard to the control: isolation, PPE, ESD strap, correct extinguisher and authorised e-waste channel.