Follow Winmate on :

How to Explain Waterproof with IP Ratings

Winmate Marketing team>November 16, 2021
What is waterproof and dust-resistant? What do the letter and numbers in IPXX stand for?
How to Explain Waterproof with IP Ratings

It is often confusing for an engineer to know what type of ingress protection requires for the device protection. Mere waterproof, water-resistant, and other descriptive labels are not helping. Fortunately, several rating systems have been developed and testing agencies to verify the results. Among these, the two well-known are NEMA and IP. In this article, we will focus on the IP system.

The IP (Ingress Protection) ratings are defined in the international standard IEC/EN 60529, which classifies the levels of sealing effectiveness of electrical enclosures against the intrusion of solid objects, dust, accidental contact, and water. The standard aims to provide users with more detailed information than vague marketing terms such as waterproof.

Code Breakdown

The IP rating is usually shown as the letters IP followed by two digits and optional letter(s).

Code letters First digit: Protection against solid particles Second digit: Liquid ingress protection Third digit: Mechanical impact resistance Additional letter: Other protections Supplementary letter: Other protections
IP Single numeral:0–6 or letter X Single numeral:0–8 or letter X Single numeral:0–9 Single letter:A, B, C, D Single letter:F, H, M, S
Mandatory Mandatory Mandatory No longer used Optional Optional

The two numeric digits indicate conformity with the conditions summarized in the tables below. The digit is replaced with the letter X when insufficient data has been gathered to assign a protection level

First Digit Intrusion Protection Second Digit Moisture Protection
0 No protection. 0 No protection.
1 Protected against solid objects bigger than 50mm, e.g., back of the hands. 1 Protected against vertically falling drops of water, e.g., condensation.
2 Protected against solid objects over 12.55 mm, e.g., fingers. 2 Protected against dripping water at 15 degrees from the vertical.
3 Protected against solid objects over 2.5mm, e.g., tools and thick cables. 3 Protected against direct sprays of water up to 60 degrees from the vertical.
4 Protected against solid objects over 1mm, e.g., wires, screws, and small insects. 4 Protected against water splashed from all directions.
5 Protected against a limited quantity of dust ingress. 5 Protected against low-pressure jets of water from any angle.
6 Totally protected against dust. 6 Protected against strong jets of water from all directions.
7 Protected against submersion of up to 1 m depth.
8 Protected against submersion of 1 m or more. The manufacturer should specify test time and depth.
9K Protected against powerful 80 °C (176 °F) water jets

The third digit was removed from the IP Code and moved to the separate IK Code specified in EN-62262. Although no longer used, you may still find it on older electrical casings and enclosures. On the other hand, the IP code occasionally has an additional letter at the end of it. These letters are used to denote extra protections not covered in the primary two digits.

Additional letter (optional)

For the protection of personnel against access to hazardous parts with:

Letter Meaning
A Hand
B Finger
C Tool
D Wire
Supplementary letter (optional)

For the protection of equipment specific to:

Letter Meaning
F Oil resistant
H High voltage device
M Motion during water test
S Stationary during water test
Which IP Rating Do I Need?

To answer this question, it ultimately depends on the environment in which your devices will be installed, whether they will be subjected to dust, debris, or liquids. Typically, lower IP ratings are used for indoor settings where jetting water will not be an issue. High-IP-rated fixtures are used for outdoor locations subjected to greater liquids and dust, such as fields, beachfront areas, dirty warehouses, etc.

The type of works also needs to be taken into consideration. For example, work in a meat production factory. The IP69K device might be the best choice since cleaning the facility requires high-pressure hot water. But if you are working in an industry which likely to use powerful jet of lower temperature water, you might want to consider IP65 device.

Learn more on