Light bulbs for automobiles are made in several standardized series. Bulbs used for

headlamp A headlamp is a lamp attached to the front of a vehicle to illuminate the road ahead. Headlamps are also often called headlights, but in the most precise usage, ''headlamp'' is the term for the device itself and ''headlight'' is the term for t ...

s, turn signals and brake lamps may be required to comply with international and national regulations governing the types of lamps used. Other

automotive lighting Automotive lighting is functional exterior lighting in vehicles. A motor vehicle has lighting and signaling devices mounted to or integrated into its front, rear, sides, and, in some cases, top. Various devices have the dual function of illumin ...

applications such as auxiliary lamps or interior lighting may not be regulated, but common types are used by many automotive manufacturers.

International

The World Forum for Harmonization of Vehicle Regulations (ECE Regulations) develops and maintains international-consensus UN Regulations on light sources acceptable for use in lamps on vehicles and trailers type-approved for use in countries that recognise the UN Regulations. These include Regulation 37,ECE Regulation No. 37: Uniform Provisions Concerning the Approval of Filament Lamps for Use in Approved Lamp Units on Power-Driven Vehicles and of their Trailers, Revision 7
/ref> which contains specifications for filament lamps, and Regulation 99 and its addendaECE Regulation No. 99: Uniform Provisions Concerning the Approval of Light Sources for Use in Approved Gas-Discharge Lamp Units of Power-Driven Vehicles
/ref> which covers light sources for

high-intensity discharge High-intensity discharge lamps (HID lamps) are a type of Electric light, electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused ...

headlamps. Some UN-approved bulb typesTypes of bulbs and socles
/ref> are also permitted by some other regulations, such as those of the United States or of Japan, though Japan has begun supplanting the former Japanese national regulations with the international UN regulations.

Filament lamps

UN Regulation 37 covers motor vehicle filament lamps. These are categorized in three groups: those without general restriction that can be used in any application, those acceptable only for signalling lights (not for road illumination lamps), and those no longer allowable as light sources for new type approvals but still permitted for production as replacement parts.

Group 1

Group 2

Group 3

Gas discharge lamps

UN Regulation 99 covers gas discharge light sources for use in vehicle headlamps. All light sources acceptable under Regulation 99 are also acceptable under US regulations.

Germany

There is a German national regulation for vehicle bulbs, now superseded by international ECE regulations. Bulbs according to the old German regulation are still manufactured. The German regulation is contained in §22a, Subsection 1, No. 18 of the ''Straßenverkehrs-Zulassungs-Ordnung'' (StVZO, Road Traffic Approval Regulation). Per the ''Fahrzeugteileverordnung'' (FzTV, Vehicle Parts Regulation), such light bulbs must bear an approval mark consisting of a

sine wave A sine wave, sinusoidal wave, or sinusoid (symbol: ∿) is a periodic function, periodic wave whose waveform (shape) is the trigonometric function, trigonometric sine, sine function. In mechanics, as a linear motion over time, this is ''simple ...

and the letter 'K'. The technical requirements themselves are established by standards produced by DIN.

United States and Canada

In the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, entry 49 CFR 564 in the

Code of Federal Regulations In the law of the United States, the ''Code of Federal Regulations'' (''CFR'') is the codification of the general and permanent regulatory law, regulations promulgated by the executive departments and agencies of the federal government of the ...

requires manufacturers of headlight bulbs, officially known as "replaceable light sources", to furnish the

National Highway Traffic Safety Administration The National Highway Traffic Safety Administration (NHTSA ) is an agency of the U.S. federal government, part of the Department of Transportation, focused on automobile safety regulations. NHTSA is charged with writing and enforcing Feder ...

(NHTSA) with product specifications at least 60 days prior to first use. The specifications supplied by the manufacturer, on approval by NHTSA, are entered in Federal docket NHTSA-1998-3397.NHTSA Docket 1998-3397: Replaceable Light Source Information
/ref> From then on, any light source made and certified by any manufacturer as conforming to the specifications is legal for use in headlamps certified as conforming to Federal Motor Vehicle Safety Standard 108. Light sources for vehicle lamps other than headlamps are not Federally regulated. In

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

, vehicle headlamps may use light sources (bulbs) conforming to either the US or the international ECE regulations.Canada Motor Vehicle Safety Standard 108

Other countries

References

{{CarDesign nav Auto parts Automotive lamps