IP66 vs IP29K
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP66 and IP29K are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 6 vs 2) and liquid protection (level 6 vs 9K). IP66 is rated for dust-tight and powerful water jets (12.5 mm nozzle), while IP29K provides > 12.5 mm — finger and high-pressure, high-temp water jets.
IP66 is dust-tight and resists powerful water jets (12.5 mm nozzle, 100 kPa). A robust outdoor rating for equipment exposed to heavy rain, storms, or directed high-pressure hosing (but not high-pressure washdown).
With IP29K, an enclosure receives protection against solid objects larger than 12.5 mm and resistance to high-pressure (8–10 MPa), high-temperature (80 °C) water jets. It is an IEC 60529 ingress protection code combining first-digit (solid) level 2 with second-digit (liquid) level 9K.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP66
6 — Dust-Tight
IP29K
2 — > 12.5 mm — Finger
Liquid protection (second digit)
IP66
6 — Powerful Water Jets (12.5 mm nozzle)
IP29K
9 — High-Pressure, High-Temp Water Jets
Dust-tight
IP66
Yes
IP29K
No
Water-jet resistant
IP66
Yes
IP29K
Yes
Submersible
IP66
No
IP29K
Yes
Outdoor suitable
IP66
Yes
IP29K
Yes
The exact difference (IP66 vs IP29K)
Solid protection
IP66
Level 6 — Dust-Tight
IP29K
Level 2 — > 12.5 mm — Finger
IP66 provides "Dust-Tight" (level 6), while IP29K provides "> 12.5 mm — Finger" (level 2). IP66 is 4 levels higher.
Liquid protection
IP66
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP29K
Level 9 — High-Pressure, High-Temp Water Jets
IP66 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)), while IP29K handles 8–10 MPa (High-Pressure, High-Temp Water Jets). IP29K provides 3 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP66 offers higher overall protection than IP29K. Choose IP66 for harsher environments; IP29K may suffice for milder conditions and can be more cost-effective.