IP37 vs IP49K
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP37 and IP49K are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 3 vs 4) and liquid protection (level 7 vs 9K). IP37 is rated for > 2.5 mm — tool / wire and temporary immersion (up to 1 m), while IP49K provides > 1 mm — small wires and high-pressure, high-temp water jets.
Specified under IEC 60529, IP37 denotes protection against solid objects larger than 2.5 mm and protection against the effects of temporary immersion in water. Ingress of water in quantities causing harmful effects shall not be possible.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 3 with second-digit (liquid) level 7.
Built to withstand protection against solid objects larger than 1.0 mm and resistance to high-pressure (8–10 MPa), high-temperature (80 °C) water jets. Classified as IEC 60529 ingress protection code IP49K, it pairs solid level 4 with liquid level 9K.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP37
3 — > 2.5 mm — Tool / Wire
IP49K
4 — > 1 mm — Small Wires
Liquid protection (second digit)
IP37
7 — Temporary Immersion (up to 1 m)
IP49K
9 — High-Pressure, High-Temp Water Jets
Dust-tight
IP37
No
IP49K
No
Water-jet resistant
IP37
Yes
IP49K
Yes
Submersible
IP37
Yes
IP49K
Yes
Outdoor suitable
IP37
Yes
IP49K
Yes
The exact difference (IP37 vs IP49K)
Solid protection
IP37
Level 3 — > 2.5 mm — Tool / Wire
IP49K
Level 4 — > 1 mm — Small Wires
IP37 provides "> 2.5 mm — Tool / Wire" (level 3), while IP49K provides "> 1 mm — Small Wires" (level 4). IP49K is 1 level higher.
Liquid protection
IP37
Level 7 — Temporary Immersion (up to 1 m)
IP49K
Level 9 — High-Pressure, High-Temp Water Jets
IP37 handles Hydrostatic ~10 kPa at 1 m (Temporary Immersion (up to 1 m)), while IP49K handles 8–10 MPa (High-Pressure, High-Temp Water Jets). IP49K provides 2 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP49K offers higher overall protection than IP37. Choose IP49K for harsher environments; IP37 may suffice for milder conditions and can be more cost-effective.