IP ratings explained for emergency vehicle lighting, cameras and chargers
Written by Shmaya Krinsky, K&K Emergency Systems, Opa-locka, Florida. We build and upfit ambulances, fire apparatus and police vehicles, and we sell the parts we install. Updated October 2026.
Exterior equipment on an emergency vehicle lives in rain, road spray and pressure washing; cab and compartment equipment faces a different set of conditions. The IP rating on a datasheet tells you what the housing is rated to keep out, within the limits of a defined test. Here is how to read it, what it does not tell you, and what we specify for each location on a vehicle.
What "IP" means
The ratings come from the international standard IEC 60529. IP is commonly called "Ingress Protection"; IEC's own term is the International Protection code. An IP code is the letters IP followed by two characteristic numerals. The first numeral (0 to 6) rates protection against access to hazardous parts and against solid objects and dust. The second numeral (0 to 9) rates protection against water. An X in either position means that characteristic is not specified; it does not tell you whether the test was run or failed. Optional letters can follow the numerals.
An IP code addresses specified protection against access to hazardous parts and ingress of solid objects and water. It does not establish corrosion resistance, protection against condensation, UV resistance or vibration resistance. Those are separate tests.
First numeral: access, solids and dust
| Numeral | Protected against |
|---|---|
| 0 | No rated protection |
| 1 | Objects 50 mm in diameter and greater; back-of-hand access |
| 2 | Objects 12.5 mm in diameter and greater; finger access |
| 3 | Objects 2.5 mm in diameter and greater; tool access |
| 4 | Objects 1 mm in diameter and greater; wire access |
| 5 | Dust protected: some dust may enter but not enough to impair operation or safety |
| 6 | Dust tight: no dust ingress in the prescribed vacuum-assisted test |
Second numeral: water
| Numeral | Protected against |
|---|---|
| 0 | No rated protection |
| 1 | Vertically dripping water |
| 2 | Dripping water with the enclosure tilted up to 15 degrees |
| 3 | Spraying water up to 60 degrees either side of vertical |
| 4 | Splashing water from any direction |
| 5 | Water jets from a 6.3 mm nozzle, any direction |
| 6 | Powerful water jets from a 12.5 mm nozzle, any direction |
| 7 | Temporary immersion for 30 minutes. For enclosures under 850 mm tall, the bottom sits 1 m below the surface; for enclosures 850 mm tall or taller, the top sits 150 mm below the surface. "1 meter for 30 minutes" is the usual shorthand for small devices. |
| 8 | Continuous immersion under conditions more severe than IPX7, specified by the manufacturer or agreed with the buyer. Check the stated depth and duration. |
| 9 | High-pressure, high-temperature water jets at close range. IEC 60529 calls this IPX9. The automotive IP69K designation comes from the German DIN 40050-9 standard, since replaced by ISO 20653, and is a separate test. A datasheet should say which standard was used. |
Two rules that matter in practice. First, water numerals up to 6 are cumulative: a higher rating in that range implies the lower ones. Second, 7, 8 and 9 are not cumulative with 5 and 6. A product rated IP67 passed an immersion test but was not necessarily tested against water jets. To document both, look for a dual rating such as "IP66/IP67" or "IP66/IP68". A rating of "IP67/IP69K" documents immersion plus the separate hot high-pressure test; it does not by itself document IPX6.
Ratings you will see on emergency vehicle equipment
These are examples of what the ratings mean, not rules about which equipment must carry them. Real products vary: Federal Signal's Allegiant lightbar, a complete exterior assembly, is rated IP65.
| Rating | Means | Examples of where it appears |
|---|---|---|
| IP65 | Dust tight, protected against the defined water-jet test | Federal Signal Allegiant lightbar |
| IP66 | Dust tight, protected against the defined powerful-jet test | Exterior equipment; does not by itself establish suitability for close-range or hot pressure washing |
| IP67 | Dust tight, temporary immersion as defined above | Federal Signal MicroPulse C perimeter light (manufacturer lists IP67) |
| IP68 | Dust tight, more severe immersion as stated by the manufacturer | Lightheads and cameras in low or wet locations; check the stated conditions |
| IP69K | Dust tight plus the specified automotive hot high-pressure test; check the documented standard and code | Equipment specified for hot pressure washing; follow the product's cleaning instructions |
What we specify by location
This is K&K's shop practice, not a requirement of any standard. Match the rating to the actual exposure and to the manufacturer's installation and cleaning instructions.
- Grille, bumper and lower-body lightheads: we specify IP67 or better for immersion. If the apparatus is pressure washed, we look separately for a jet or wash rating (IP66, IPX9 or IP69K) and the manufacturer's cleaning limits. IP68 is a more-severe immersion rating under specified conditions, not a pressure-washing upgrade; compare the declared depth and duration.
- Lightbars: check the rating of the complete assembly, not only the modules inside it.
- Siren speakers: ingress protection depends on the acoustic and enclosure design. Check the model's environmental rating and install it the way the manufacturer specifies. Whelen's SA315 installation guide, for example, locates its wire and drain opening at the bottom; follow the instructions for your model rather than a general rule.
- Backup and side cameras: we specify IP67 or better and check the connector rating separately. In our experience, water in the connector, not the camera body, is the usual failure we repair.
- Shoreline and charger inlets: the rating can differ with the cover closed, open and connected. Kussmaul's manual for one of its Auto Eject inlets lists IP65 with the cover closed and IP44 open. Check each condition for your model.
- Inside the cab or a sealed compartment: IP54 or IP65 is often adequate, but consider cleaning, spills and condensation in that compartment before deciding.
IP ratings versus NEMA ratings
Some enclosures, relays and power distribution modules carry a NEMA enclosure type (NEMA 4, 4X, 6, 6P) instead of an IP code. NEMA types come from a US standard and include things IP codes do not, such as corrosion protection (the X in 4X) and external icing for outdoor types. NEMA publishes a one-direction comparison table: it maps NEMA Types 4 and 4X to IP66, Type 6 to IP67 and Type 6P to IP68 for the ingress characteristics. The reverse is not true; an IP66 product is not thereby a NEMA 4X enclosure. If a datasheet lists both, ask for the basis of each claim and select against the exposures you actually have.
What an IP rating does not tell you
- UV and heat. An IP68 lens can still yellow in Florida sun; we have seen it happen within a few years. Look for UV-stabilized, hard-coated polycarbonate lenses or ask the manufacturer about lens weathering.
- Salt spray. Corrosion is a separate test. ASTM B117 is a common salt-fog practice, but it defines the exposure, not a pass or fail. If you buy for a coastal department, ask for the method, the exposure duration, the material tested and the acceptance criteria.
- Vibration. Not covered by IP. The SAE warning-light standards include vibration for warning devices; cameras, chargers and speakers are qualified separately by their manufacturers. See our post on SAE J595 and J845 classes.
- The wiring behind it. A rated housing does not rate the splice behind it. In our shop, the water failures we trace most often are unsealed connections behind the device, not the device itself. Our practice is heat-shrink sealed connectors, drip loops and the manufacturer's routing instructions.
Frequently asked questions
Is IP68 always better than IP67? For immersion, IP68 is the more severe rating, but compare the declared conditions for the actual product. For pressure washing, neither says anything; look for a jet or wash rating.
Can I pressure wash an IP67 lighthead? IP67 does not authorize pressure washing. Follow the manufacturer's approved cleaning method and limits. There is no universal safe distance implied by an IP rating.
Why do some products list "IP67/IP69K"? Because the two tests cover different threats, immersion and hot high-pressure spray, and the manufacturer claims both. The label is a claim; the product's test documentation is the evidence.
What does IPX7 mean? Rated for temporary immersion (7), with the solids characteristic not specified (X). For exterior vehicle equipment, we ask for a full two-numeral rating.
Browse our emergency lighting, camera systems and sirens and speakers, or call (305) 317-2619 and we will help you match the rating to each location on your vehicle.
About this article: it was drafted with AI assistance, fact-checked against IEC, ISO, NEMA, ASTM and manufacturer sources, and reviewed by K&K Emergency Systems. Standards change and errors are possible. Where we describe our own practice, it is our practice, not a requirement of any standard. Confirm any requirement with the standard, the manufacturer, or with us before you buy or install.