A second code that quietly ships on the same datasheet as IP. What the joules mean, where you actually need IK08 or IK10, and the test that decides the badge.
Four ideas to carry into the next specification conversation you have.
Defined in IEC 62262. Rates how much kinetic energy the enclosure absorbs without compromising the IP rating.
IK01 = 0.14 J (a child's tap). IK10 = 20 J (a 5 kg mass dropped from 40 cm). Most outdoor LED housings target IK08 (5 J).
Forklifts, ladders, sand, and the occasional rock from a passing truck. Below IK08 and you replace lenses, not bulbs.
PC absorbs energy mostly by deformation: it can dent, crack or come out of its frame, depending on thickness, ageing and fixing. Tempered glass resists by hardness and can fragment beyond the limit. The test report decides what each build earns.
Energy delivered by a pendulum hammer or vertical drop, per IEC 62262.
| IK code | Impact energy | Typical application |
|---|---|---|
| IK00 | Unprotected | Decorative interior only |
| IK02 | 0.2 J | Office downlights |
| IK04 | 0.5 J | Schools · public corridors |
| IK06 | 1.0 J | Retail · car-park ceilings |
| IK07 | 2.0 J | Warehouse aisles |
| IK08 | 5.0 J | Street · tunnel · industrial |
| IK09 | 10 J | Vandal-prone · prisons |
| IK10 | 20 J | Stadium · transit · ATM canopies |
The badge is earned on a bench, not on paper: a known mass, a known drop height, one measured blow, per IEC 62262 with IEC 60068-2-75.
Five things people miss when they sign off on an IK rating.
IEC 62262 fixes a steel hammer mass and drop angle to deliver a defined joule energy at a defined velocity. The fixture must keep its IP rating after, not just keep its shape. "Looks fine" is not a pass.
Tempered glass resists mostly by hardness; beyond the limit it can fragment, and whether it stays in place depends on the frame and the construction. Polycarbonate absorbs energy mostly by deformation; it can dent, crack or come out of place depending on thickness, ageing and the fixing method. Where pieces can fall on people, weigh the material and the fixing method together.
IK10 says the fixture survives a 5 kg mass from 40 cm. A determined attacker with a hammer exceeds that. "Vandal-resistant" is a delay, not a guarantee. For stations and prisons, pair IK10 with mounting that is harder to access.
An IK10 spec on the diffuser does not automatically apply to the body. Read the test report, some lights ship IK10 lens, IK02 body. The weak point is the failure point.
Replacing a fluorescent fixture with an LED retrofit kit often drops IK rating. The old housing was metal; the retrofit lens is plastic. Re-verify IK at handover.
Our highbay, streetlight, and tunnel ranges default to IK08; IK10 polycarbonate diffusers ship standard for transit and stadium projects.
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