"Mechanical testing" covers a surprisingly wide range of genuinely distinct physical stresses, and conflating them is a common gap in test planning. Sustained vibration during transport, a single shock impact from a drop, and an external impact against an installed enclosure are three different events, each governed by its own IEC standard, each requiring its own test apparatus.
Vibration Testing — Sustained, Repeated Stress
Vibration testing subjects a product to continuous oscillating motion over an extended period. IEC 60068-2-6 covers sinusoidal vibration testing — useful for finding specific resonant frequencies. IEC 60068-2-64 covers broadband random vibration testing — closer to genuinely random, multi-frequency real-world vibration profiles.
The failure mechanisms vibration testing targets are fundamentally about cumulative fatigue — repeated flexing that gradually weakens solder joints, loosens fasteners, or fatigues structural members over the test duration, rather than a single overstress event.
Shock Testing — A Single, Severe Event
Shock testing, primarily under IEC 60068-2-27, applies a defined, controlled pulse of acceleration — simulating a single transient mechanical event: a drop during handling, a sudden jolt during transport, or an impact during installation.
Drop testing — covered by related standards like ISO 2248 — is a specific, commonly required subset of shock testing, simulating free-fall drops from a specified height onto a hard surface.
Impact (IK) Testing — External Impact Against an Installed Product
A third, genuinely distinct category covers a product's resistance to external mechanical impact once it's installed and in service. This is governed by IEC 62262 (the IK rating system) and tested per IEC 60068-2-75, using either a pendulum impact hammer or a vertical drop-weight device.
The IK rating scale runs from IK00 (no protection) through IK10 (the highest standard rating, 20 Joules).
Why These Three Get Confused — and Why That Matters
| Test type | What's being simulated | Standard | Apparatus |
|---|---|---|---|
| Vibration | Sustained transport/operational vibration | IEC 60068-2-6 (sine), 2-64 (random) | Electrodynamic vibration table |
| Shock | Single transient event | IEC 60068-2-27 | Shock test bench |
| Impact (IK) | External impact against an installed, in-service product | IEC 62262 / IEC 60068-2-75 | Pendulum hammer or drop-weight tester |
Equipment Considerations
Vibration tables are specified primarily by table size, maximum load capacity, frequency range, and achievable acceleration.
Shock test benches are specified by waveform types, achievable peak acceleration and pulse duration, and maximum sample mass.
IK pendulum and drop-weight testers are specified by the impact energy range they cover and precision of impact point positioning.
Practical Test Program Guidance
For products with genuine transport exposure, both vibration and shock/drop testing are typically relevant. For products with an IK rating claim, impact testing is a distinct requirement from transport testing. For equipment near rotating machinery, sinusoidal testing at frequencies representative of the actual machinery gives more targeted data.