IP40 vs IP39K
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP40 and IP39K are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 4 vs 3) and liquid protection (level 0 vs 9K). IP40 is rated for > 1 mm — small wires and no protection, while IP39K provides > 2.5 mm — tool / wire and high-pressure, high-temp water jets.
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.
IP39K is an ingress protection code that ensures protection against solid objects larger than 2.5 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 3 with second-digit (liquid) level 9K.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP40
4 — > 1 mm — Small Wires
IP39K
3 — > 2.5 mm — Tool / Wire
Liquid protection (second digit)
IP40
0 — No Protection
IP39K
9 — High-Pressure, High-Temp Water Jets
Dust-tight
IP40
No
IP39K
No
Water-jet resistant
IP40
No
IP39K
Yes
Submersible
IP40
No
IP39K
Yes
Outdoor suitable
IP40
No
IP39K
Yes
The exact difference (IP40 vs IP39K)
Solid protection
IP40
Level 4 — > 1 mm — Small Wires
IP39K
Level 3 — > 2.5 mm — Tool / Wire
IP40 provides "> 1 mm — Small Wires" (level 4), while IP39K provides "> 2.5 mm — Tool / Wire" (level 3). IP40 is 1 level higher.
Liquid protection
IP40
Level 0 — No Protection
IP39K
Level 9 — High-Pressure, High-Temp Water Jets
IP40 provides "No Protection" (level 0), while IP39K provides "High-Pressure, High-Temp Water Jets" (level 9). IP39K is 9 levels higher.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP39K offers higher overall protection than IP40. Choose IP39K for harsher environments; IP40 may suffice for milder conditions and can be more cost-effective.