IP31 vs IP40
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP31 and IP40 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 3 vs 4) and liquid protection (level 1 vs 0). IP31 is rated for > 2.5 mm — tool / wire and vertically dripping water, while IP40 provides > 1 mm — small wires and no protection.
The IP31 rating offers protection against solid objects larger than 2.5 mm and protection against vertically falling drops of water. Dripping water shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 3 with second-digit (liquid) level 1.
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.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP31
3 — > 2.5 mm — Tool / Wire
IP40
4 — > 1 mm — Small Wires
Liquid protection (second digit)
IP31
1 — Vertically Dripping Water
IP40
0 — No Protection
Dust-tight
IP31
No
IP40
No
Water-jet resistant
IP31
No
IP40
No
Submersible
IP31
No
IP40
No
Outdoor suitable
IP31
No
IP40
No
The exact difference (IP31 vs IP40)
Solid protection
IP31
Level 3 — > 2.5 mm — Tool / Wire
IP40
Level 4 — > 1 mm — Small Wires
IP31 provides "> 2.5 mm — Tool / Wire" (level 3), while IP40 provides "> 1 mm — Small Wires" (level 4). IP40 is 1 level higher.
Liquid protection
IP31
Level 1 — Vertically Dripping Water
IP40
Level 0 — No Protection
IP31 provides "Vertically Dripping Water" (level 1), while IP40 provides "No Protection" (level 0). IP31 is 1 level higher.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP31 and IP40 offer comparable overall protection; choose based on the specific protection dimension (dust vs. water) that matters most for your application.