IP33 vs IP37
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP33 and IP37 are both IEC 60529 ingress protection codes, but they differ in liquid protection (level 3 vs 7). IP33 is rated for > 2.5 mm — tool / wire and spraying water (up to 60°), while IP37 provides > 2.5 mm — tool / wire and temporary immersion (up to 1 m).
IP33 protects against tools and 2.5 mm objects plus spraying water up to 60° from vertical. A practical rating for indoor equipment subject to light spray or for sheltered outdoor fixtures.
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.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP33
3 — > 2.5 mm — Tool / Wire
IP37
3 — > 2.5 mm — Tool / Wire
Liquid protection (second digit)
IP33
3 — Spraying Water (up to 60°)
IP37
7 — Temporary Immersion (up to 1 m)
Dust-tight
IP33
No
IP37
No
Water-jet resistant
IP33
No
IP37
Yes
Submersible
IP33
No
IP37
Yes
Outdoor suitable
IP33
No
IP37
Yes
The exact difference (IP33 vs IP37)
Solid protection
IP33
Level 3 — > 2.5 mm — Tool / Wire
IP37
Level 3 — > 2.5 mm — Tool / Wire
Both IP33 and IP37 share the same solid protection: > 2.5 mm — Tool / Wire.
Liquid protection
IP33
Level 3 — Spraying Water (up to 60°)
IP37
Level 7 — Temporary Immersion (up to 1 m)
IP33 handles 80 kPa (tube) / 50 kPa (nozzle) (Spraying Water (up to 60°)), while IP37 handles Hydrostatic ~10 kPa at 1 m (Temporary Immersion (up to 1 m)). IP37 provides 4 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP37 offers higher overall protection than IP33. Choose IP37 for harsher environments; IP33 may suffice for milder conditions and can be more cost-effective.