IK Ratings Explained

What is an IK Rating?

The IK rating system is defined by international standard IEC 62262. It classifies the level of protection provided by the enclosure of electrical equipment — including LED luminaires — against external mechanical impacts.

An IK rating is expressed as a two-digit code from IK00 to IK10, where the number indicates the energy (in joules) of impact the enclosure can withstand without compromising its protective function. Unlike IP ratings (which measure protection against dust and water), IK ratings specifically measure resistance to physical force — drops, kicks, thrown objects and deliberate vandalism.

The IK test involves striking the enclosure with a calibrated hammer or pendulum at defined energy levels. The luminaire passes if the enclosure maintains its integrity and continues to function correctly after the impact.

IK Rating Scale

The IK scale runs from IK00 (no protection) to IK10 (maximum protection):

• IK00 — No protection against impact • IK01 — 0.15 joules (equivalent to a 0.25kg mass dropped from 60mm) • IK02 — 0.20 joules (0.25kg from 80mm) • IK03 — 0.35 joules (0.25kg from 140mm) • IK04 — 0.50 joules (0.25kg from 200mm) • IK05 — 0.70 joules (0.25kg from 280mm) • IK06 — 1.00 joule (0.25kg from 400mm) • IK07 — 2.00 joules (0.50kg from 400mm) • IK08 — 5.00 joules (1.70kg from 300mm) • IK09 — 10.00 joules (5.00kg from 200mm) • IK10 — 20.00 joules (5.00kg from 400mm)

The jump in energy between ratings is significant — IK10 provides 40 times more impact resistance than IK04. This is why specifying the correct IK rating for each environment is critical to avoiding premature luminaire failure and costly replacements.

Which IK Rating Do I Need?

The required IK rating depends on the risk profile of the installation environment:

• IK02–IK04 — Standard interior environments with low risk of impact: offices, meeting rooms, hotel bedrooms, residential corridors. Most recessed downlights and ceiling panels fall into this range.

• IK06–IK07 — Moderate-risk environments: covered car parks, communal corridors in residential buildings, retail back-of-house, school corridors and circulation areas. Luminaires in these locations are exposed to trolley impacts, passing equipment and occasional accidental contact.

• IK08 — Higher-risk environments: schools (classrooms and sports halls), hospitals, public buildings, transport hubs and open car parks. This is the most commonly specified IK rating for education and healthcare projects, balancing robust protection with reasonable cost.

• IK09–IK10 — Maximum protection environments: custodial and secure facilities, mental health units, police custody suites, public toilets, subway stations, underpasses and any location where deliberate vandalism or extreme accidental impact is expected. IK10 luminaires are designed to withstand sustained, deliberate attack.

Many project specifications — particularly in the public sector — now mandate minimum IK ratings alongside IP ratings in tender documentation.

IK Ratings by Sector

• Education — IK08 is the standard requirement for classrooms, corridors and sports halls under BB93 and Education Funding Agency guidelines. Sports halls and gymnasia may require IK10 where ball impact is expected.

• Healthcare — IK08 minimum for general circulation areas. Mental health and behavioural health units typically require IK10 anti-ligature luminaires with tamper-proof fixings.

• Car Parks — IK08 for covered multi-storey car parks. Open-deck car parks exposed to weather and vehicle-related impacts may warrant IK10.

• Custodial & Secure — IK10 is mandatory. Luminaires must also be anti-ligature (no points from which a cord or fabric can be attached) and tamper-proof (requiring specialist tools for access).

• Social Housing — IK08–IK10 for communal areas, stairwells and external walkways where vandalism risk is elevated.

• Retail — IK04–IK06 for sales floors; IK08 for loading bays, goods-in areas and back-of-house corridors.

• Industrial — IK08 minimum for production floors and warehouses. IK10 for environments with overhead cranes, forklifts or heavy moving equipment.

EOS offers IP65/IK10 rated luminaires across our weatherproof, bulkhead and secure ranges — purpose-built for demanding environments.

IK Ratings and IP Ratings — What's the Difference?

IP and IK ratings measure fundamentally different types of protection and should always be considered together:

• IP (Ingress Protection) — measures protection against dust (first digit) and water (second digit). Example: IP65 = dust-tight + water jet protection.

• IK (Impact Protection) — measures resistance to mechanical impact, expressed in joules of energy. Example: IK10 = 20 joules impact resistance.

A luminaire can be IP65 (fully weatherproof) but only IK02 (minimal impact resistance) — meaning it will keep water out but shatter on the first impact. Conversely, a luminaire can be IK10 (extremely impact-resistant) but only IP20 (no water protection).

For exterior, car park, industrial and public-realm applications, both ratings must be specified together. The most common high-performance combination is IP65/IK10 — dust-tight, water-jet-proof and vandal-resistant.

All EOS luminaires carry independently tested and certified IP and IK ratings, with test documentation available on request.

Construction and Materials

Achieving high IK ratings requires careful material selection and construction design:

• Polycarbonate diffusers — high-impact polycarbonate is the standard diffuser material for IK08+ luminaires. It offers excellent impact resistance, light transmission and UV stability. Opal polycarbonate diffusers provide uniform light distribution while withstanding significant mechanical force.

• Die-cast aluminium housings — aluminium provides a strong, lightweight enclosure that dissipates heat effectively and resists corrosion. Die-cast construction ensures consistent wall thickness and structural integrity.

• Stainless steel fixings — tamper-proof stainless steel screws (typically pin-Torx or snake-eye security heads) prevent unauthorised access and resist corrosion in exterior and wet environments.

• Gasket sealing — silicone or EPDM gaskets maintain IP rating integrity even after impact, ensuring the luminaire remains weatherproof throughout its operational life.

• Anti-ligature design — for custodial and mental health environments, luminaires must eliminate any projection or recess that could be used as a ligature point. This requires flush-mounted, radiused enclosures with concealed fixings.

EOS designs and manufactures luminaires with these principles built in — not applied as afterthoughts. Our secure and weatherproof ranges are engineered from the ground up for high-impact environments.