IP15 vs IP66
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP15 and IP66 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 1 vs 6) and liquid protection (level 5 vs 6). IP15 is rated for > 50 mm — back of hand and water jets (6.3 mm nozzle), while IP66 provides dust-tight and powerful water jets (12.5 mm nozzle).
With IP15, an enclosure receives protection against solid objects larger than 50 mm and protection against water jets. Water projected by a 6.3 mm nozzle against the enclosure from any direction shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 1 with second-digit (liquid) level 5.
IP66 is dust-tight and resists powerful water jets (12.5 mm nozzle, 100 kPa). A robust outdoor rating for equipment exposed to heavy rain, storms, or directed high-pressure hosing (but not high-pressure washdown).
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP15
1 — > 50 mm — Back of Hand
IP66
6 — Dust-Tight
Liquid protection (second digit)
IP15
5 — Water Jets (6.3 mm nozzle)
IP66
6 — Powerful Water Jets (12.5 mm nozzle)
Dust-tight
IP15
No
IP66
Yes
Water-jet resistant
IP15
Yes
IP66
Yes
Submersible
IP15
No
IP66
No
Outdoor suitable
IP15
Yes
IP66
Yes
The exact difference (IP15 vs IP66)
Solid protection
IP15
Level 1 — > 50 mm — Back of Hand
IP66
Level 6 — Dust-Tight
IP15 provides "> 50 mm — Back of Hand" (level 1), while IP66 provides "Dust-Tight" (level 6). IP66 is 5 levels higher.
Liquid protection
IP15
Level 5 — Water Jets (6.3 mm nozzle)
IP66
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP15 handles 30 kPa (Water Jets (6.3 mm nozzle)), while IP66 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)). IP66 provides 1 level more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP66 offers higher overall protection than IP15. Choose IP66 for harsher environments; IP15 may suffice for milder conditions and can be more cost-effective.