IP40 vs IP37
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP40 and IP37 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 4 vs 3) and liquid protection (level 0 vs 7). IP40 is rated for > 1 mm — small wires and no protection, while IP37 provides > 2.5 mm — tool / wire and temporary immersion (up to 1 m).
IP40 protects against small tools and wires (1 mm objects) but offers no water protection. Useful for indoor equipment needing finer ingress protection against small debris and tools.
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)
IP40
4 — > 1 mm — Small Wires
IP37
3 — > 2.5 mm — Tool / Wire
Liquid protection (second digit)
IP40
0 — No Protection
IP37
7 — Temporary Immersion (up to 1 m)
Dust-tight
IP40
No
IP37
No
Water-jet resistant
IP40
No
IP37
Yes
Submersible
IP40
No
IP37
Yes
Outdoor suitable
IP40
No
IP37
Yes
The exact difference (IP40 vs IP37)
Solid protection
IP40
Level 4 — > 1 mm — Small Wires
IP37
Level 3 — > 2.5 mm — Tool / Wire
IP40 provides "> 1 mm — Small Wires" (level 4), while IP37 provides "> 2.5 mm — Tool / Wire" (level 3). IP40 is 1 level higher.
Liquid protection
IP40
Level 0 — No Protection
IP37
Level 7 — Temporary Immersion (up to 1 m)
IP40 provides "No Protection" (level 0), while IP37 provides "Temporary Immersion (up to 1 m)" (level 7). IP37 is 7 levels higher.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP37 offers higher overall protection than IP40. Choose IP37 for harsher environments; IP40 may suffice for milder conditions and can be more cost-effective.