IP45 vs IP18
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP45 and IP18 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 4 vs 1) and liquid protection (level 5 vs 8). IP45 is rated for > 1 mm — small wires and water jets (6.3 mm nozzle), while IP18 provides > 50 mm — back of hand and continuous immersion (manufacturer-specified).
IP45 protects against 1 mm solid objects and low-pressure water jets (6.3 mm nozzle, 30 kPa). A mid-range indoor/outdoor-covered rating for equipment that may be rinsed or hosed gently.
The IP18 classification guarantees protection against solid objects larger than 50 mm and protection against the effects of continuous immersion in water under conditions specified by the manufacturer.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 1 with second-digit (liquid) level 8.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP45
4 — > 1 mm — Small Wires
IP18
1 — > 50 mm — Back of Hand
Liquid protection (second digit)
IP45
5 — Water Jets (6.3 mm nozzle)
IP18
8 — Continuous Immersion (manufacturer-specified)
Dust-tight
IP45
No
IP18
No
Water-jet resistant
IP45
Yes
IP18
Yes
Submersible
IP45
No
IP18
Yes
Outdoor suitable
IP45
Yes
IP18
Yes
The exact difference (IP45 vs IP18)
Solid protection
IP45
Level 4 — > 1 mm — Small Wires
IP18
Level 1 — > 50 mm — Back of Hand
IP45 provides "> 1 mm — Small Wires" (level 4), while IP18 provides "> 50 mm — Back of Hand" (level 1). IP45 is 3 levels higher.
Liquid protection
IP45
Level 5 — Water Jets (6.3 mm nozzle)
IP18
Level 8 — Continuous Immersion (manufacturer-specified)
IP45 handles 30 kPa (Water Jets (6.3 mm nozzle)), while IP18 handles Specified by manufacturer (Continuous Immersion (manufacturer-specified)). IP18 provides 3 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP45 and IP18 offer comparable overall protection; choose based on the specific protection dimension (dust vs. water) that matters most for your application.