What is ESD? Describe the purpose of "pink" ESD bags? black or silvery ESD bag? How do you properly use a ground strap? When should you use a ground strap? How critical is it to use ESD protections? How do you safely move ESD-sensitive boards between different parts of a building?

ESD (electrostatic discharge) is the sudden transfer of static charge between objects at different potentials. Even discharges too small to feel (well under the human-perception threshold) can damage or degrade sensitive semiconductors—especially CMOS, MOSFET gates, and fine-geometry ICs—causing immediate failure or latent damage that fails later.

• Pink (dissipative/antistatic) bags: Pink poly bags are static-dissipative—they don't readily generate static charge (low triboelectric) and bleed charge away slowly. They are for general handling and to prevent charge buildup, but they do not provide a Faraday shield against external fields. Use them for non-charge-sensitive items or as inner packaging.
• Black or silver/metallized (conductive/shielding) bags: These provide a conductive Faraday-cage shield that keeps external static fields and discharges away from the contents. Silver metallized-film bags are the standard static-shielding bags for transporting ESD-sensitive parts and boards; black conductive bags are also conductive/shielding. Sensitive PCBs should travel inside shielding bags.

Using a ground (wrist) strap: Put the band snugly on your wrist so the conductive side contacts skin, and connect its coil cord to a proper ground point (an ESD mat's ground, a grounded bench, or building ground)—the same common ground as the equipment you're handling. The cord contains a built-in current-limiting resistor (typically ~1 MΩ) so charge bleeds off safely and slowly and so you are protected if you contact a live voltage. This keeps you and the board at the same potential, preventing a discharge through the components.

When to use it: Whenever handling bare boards or ESD-sensitive components—at the bench during assembly, rework, or test. Combine it with an ESD mat, and ideally heel straps/ESD footwear and flooring in controlled areas.

How critical: Very. ESD damage is a leading cause of electronics field failures, and latent damage can pass initial testing only to fail in the field, making it costly and hard to diagnose. Consistent ESD discipline is essential for sensitive CMOS/MOSFET parts.

Moving boards across a building: Place each board in a static-shielding (silver/metallized or conductive) bag, ideally inside an ESD-safe (conductive/dissipative) tote or container. Avoid sliding boards on insulating surfaces, handle by edges, and at the destination ground yourself (wrist strap/mat) before removing the board from its bag. Don't carry bare boards or transport them in ordinary plastic.