DOT vs E-Mark: How to Read a Vehicle Light’s Approval Marking (and What It Does Not Prove)

A DOT marking on a lamp lens is a manufacturer’s own certification of compliance with FMVSS No. 108, while an E-mark is a type approval issued by a named government authority under a UN regulation, and the two claims are not interchangeable. Reading a lens therefore means separating three separate questions: who made the claim, what document the claim points to, and whether that document covers the lamp as a component or the vehicle as a whole.

Quick answer

The marking on a lamp lens tells you which approval regime the product claims to sit in, and it does not tell you whether the lamp is legal to switch on, on a given road, in a given vehicle.

Marking	Who states it	Legal basis	What it proves
DOT on a headlamp lens	The manufacturer	49 CFR 571.108 S6.5.1	A certification, under 49 U.S.C. 30115, that the item conforms to FMVSS No. 108
DOT on any other lamp	The manufacturer, optionally	49 CFR 571.108 S6.5.1.2	The same certification; the mark itself is optional
E plus a country number and approval number	A type approval authority in a Contracting Party	UN Regulation No 148, Annex 7	A granted type approval, recorded in the authority’s communication form
e in a rectangle	A European Union approval authority	Regulation (EU) 2018/858 Article 38	A type approval mark for a component or separate technical unit
SAE plus a document code	The manufacturer	49 CFR 571.5 and 393.25	A claim of conformance to an incorporated industry standard, with no government approval number

Two approval philosophies: self-certification and type approval

The two philosophies behind those markings are structurally different, and the difference explains almost every confusing claim a supplier can make.

Self-certification puts the burden of proof on the manufacturer or importer, before the product is sold, with no pre-market approval step and no government-issued approval number. The United States uses this model under 49 U.S.C. 30115. Canada applies the same logic: the Motor Vehicle Safety Act requires manufacturers and importers to self-certify that their vehicles and equipment comply with the safety regulations. Australia also operates a self-certification system for its Australian Design Rules, with compliance established by the manufacturer rather than by a pre-issued government approval.

Type approval puts the decision in the hands of an authority that examines drawings, test reports and sometimes a physical sample, and then issues a numbered approval. The UN 1958 Agreement regulations use this model, and UN Regulation No 148 states that the applicant for approval is the holder of the trade mark, who submits drawings and technical descriptions, including the space reserved for the approval marking or the Unique Identifier. The European Union then layers its own type approval markings on top through Regulation (EU) 2018/858.

Dimension	Self-certification	Type approval
Who decides compliance	Manufacturer or importer	Approval authority in a named country
Pre-market government review	None	Drawing review, test report, sometimes a sample
What appears on the part	A symbol or standard code, at the manufacturer’s option for most lamps	A circle or rectangle with a country number, an approval number and a regulation code
What identifies the claim	The manufacturer’s certification statement	The approval number, traceable in the authority’s records
Where a buyer verifies it	The conformance statement and the test file	The approval certificate number and the issuing authority

One practical consequence of self-certification is that the paperwork trail matters more than the symbol, and every DOT vs E-mark question resolves along that fault line. Under 49 U.S.C. 30115 a person may not issue a certification if, in exercising reasonable care, that person has reason to know the certificate is false or misleading in a material respect. The certification exists whether or not any symbol is moulded into the lens, and a supplier who cannot produce the underlying test file has nothing behind the claim, even if the lens does carry the letters. The mirror-image consequence applies to type approval: a lawfully granted E-mark belongs to a specific approval number issued to a specific applicant for a specific lamp type, so a certificate that does not name the product you are buying does not back the mark on your lens.

United States: what FMVSS No. 108 actually requires on a lens

Section S6.5.1 of 49 CFR 571.108 is the clause that makes the letters mandatory, and it is narrow. A headlamp lens must be marked with the symbol DOT to indicate certification under 49 U.S.C. 30115. The same obligation extends to the lens of a beam contributor and to the replaceable lens of a headlamp. Everything else that a buyer might call a safety lamp falls outside that sentence.

Section S6.5.1.2 then does something that surprises almost every buyer who reads it for the first time. Every original equipment or replacement lamp or reflective device specified in Table I, other than a headlamp, or an item of associated equipment specified in S9, may be marked with the symbol DOT, and that marking constitutes a certification that it conforms to the requirements of the standard. The verb is “may”, so the absence of DOT on an auxiliary LED work light, a light bar, a warning light or an aftermarket fog lamp proves nothing about non-compliance, because the standard never asked for the mark on those products.

This is also the point at which the phrase “DOT approved” breaks down. Nothing in the standard describes an approval process, an approving office or an approval number for lighting equipment. A lens marked DOT has been certified by its maker, in the legal sense described in 49 U.S.C. 30115, and by nobody else.

The DOT symbol is a manufacturer’s certification, not a government approval

49 U.S.C. 30115 is the statutory source of the DOT symbol, and it is short enough to read in full. It directs that a manufacturer or distributor of a motor vehicle or item of motor vehicle equipment may not deliver the vehicle or equipment for sale unless it is certified to comply with the applicable motor vehicle safety standard. The certificate is issued by the regulated party, not by the regulator.

The statute contains a diligence clause that gives the certification its legal weight. A person may not issue the certificate if, in exercising reasonable care, that person has reason to know the certificate is false or misleading in a material respect. In other words, the certification is a statement the maker is legally bound to have investigated, and it carries exposure if it was made carelessly or dishonestly. That is the whole of the federal control at the point of sale.

The statute also distinguishes vehicles from equipment in the way the certification is displayed. Certification of a vehicle is indicated by a permanent label fixed to the vehicle. Certification of equipment may be marked on the equipment itself or on its container. For lamps and light bars, that means the federal certification statement is legally capable of appearing on the retail packaging rather than on the lamp body, and a buyer inspecting only the product may never see it.

Two further consequences deserve a place in any supplier conversation.

• There is no federal approval number for a lighting component, because the federal system does not issue one. Any supplier that prints an “approval number” next to a DOT claim is describing something the statute and the standard do not create.
• Because the certification attaches to the party that signed it, the value of a DOT claim depends on the accountability of the maker. A buyer who cannot identify the certifying entity cannot evaluate the claim.

The other symbols on a headlamp lens: trademark, voltage, model number, sealed beam code

Section S6.5.1 is not the only marking clause in 49 CFR 571.108, and the surrounding clauses are where a lens becomes readable. Section S6.5.3.1 and S6.5.3.2 require a registered trademark and the voltage and model or trade number. A sealed beam lamp must be moulded with the words “sealed beam” and an identification code, and section S6.5.3.3.1 sets the character height for that moulding at not less than 6.35 mm.

Marking	Clause	Requirement	Notes
DOT	S6.5.1	Required on headlamp and beam contributor lenses	Indicates certification under 49 U.S.C. 30115
Registered trademark	S6.5.3.1	Required on headlamps	Identifies the responsible party
Voltage and model or trade number	S6.5.3.2	Required on headlamps	Ties the lens to a product file
“sealed beam” and identification code	S6.5.3.3.1	Required on sealed beam lamps	Character height not less than 6.35 mm
HB type or discharge light source design number	S6.5.3.4.1	Required on replaceable light source headlamps, ahead of the light source	HB1 excepted
DRL	S6.5.2	Required on a lamp used as a daytime running lamp that is not optically combined with a headlamp	Character height not less than 3 mm
DOT on a non-headlamp	S6.5.1.2	Optional	Constitutes a certification if present

The practical lesson is that a headlamp lens carries a small data set: a certification symbol, an identity, an electrical specification and, where relevant, a beam or source type. A buyer who sees only the DOT symbol and none of the rest has seen the least informative part of the lens.

Where the United States does not require a lamp to be marked at all

The optional status of the DOT symbol on non-headlamps is not a loophole that manufacturers found; it is the deliberate design of the standard, and the National Highway Traffic Safety Administration’s predecessor agency said so in writing.

In a notice of proposed rulemaking published at 62 FR 18170 on 14 April 1997, the Federal Highway Administration explained that, with the exception of headlamps and beam contributors, FMVSS No. 108 does not require lamps to be marked, and that manufacturers are responsible for ensuring their products meet the applicable requirements but the lamps do not have to be marked to indicate that the device meets the standards. That sentence is the most explicit official statement of the American position, and it is frequently quoted in the wrong register: it appears in a proposed rule, not in an operative regulation, so it should be read as the agency’s explanation of the existing standard rather than as a binding instruction.

The current operative provisions remain the regulation text: section 571.108 S6.5.1 for headlamps, S6.5.1.2 for everything else, and 49 CFR 393.11 for commercial motor vehicles in service. Under S6.5.1.2, absence of the mark on a non-headlamp proves nothing in either direction.

How SAE codes become mandatory: 49 CFR 571.5

A lens or a specification sheet often carries an SAE document code, such as J759, J578, J575, J586, J592, J845, J595 or J1318, with no DOT symbol anywhere. The reason those codes carry legal weight in the United States is incorporation by reference, and the operative list is 49 CFR 571.5, which lists the publications that the Federal Motor Vehicle Safety Standards treat as part of the rule.

Document	Title as incorporated	Where it lands
SAE J759 JAN95	Lighting Identification Code	Incorporated into 49 CFR 571.121
SAE J578	Colour Specification	Cited for signal lighting colour
SAE J575	Test methods for lighting devices	Cited for lamp testing
UNECE Regulation 48	Installation of lighting and light signalling devices	Incorporated in full into 49 CFR 571.108

Section 571.108 then closes the loop, because it directs that every lamp be designed to the SAE documents that the standard cites or re-cites, and it instructs the reader that wording such as “it is recommended that”, “recommendations” and “should be” must be read as mandatory requirements rather than as advice. An SAE reference in a specification is therefore part of the federal requirement for that lamp type, not optional guidance. One boundary should be stated plainly: the specific letter codes defined inside SAE J759 are not reproduced in the regulation text, and the standard itself is a paid document that was not available for this article, so a supplier showing an SAE code on a lens should be able to produce the standard and the test report that applies it.

Additional and replacement lamps: S6.2.1 and S6.7.1

Two short clauses in 49 CFR 571.108 decide most disputes about aftermarket lighting, and neither of them is about markings.

Section S6.2.1 states that no additional lamp, reflective device or other motor vehicle equipment is permitted to be installed that impairs the effectiveness of lighting equipment required by the standard. Section S6.2.2 addresses the related case where an added item obstructs a lamp that the standard requires and provides that the function must be preserved, so adding equipment is lawful only while the required lighting keeps working as required. Section S6.7.1.1 requires a replacement lamp to satisfy all the requirements of the lamp it replaces and to provide all of its functions, and section S6.7.1.2 requires that, when installed, the replacement does not take the vehicle out of compliance with the standard, judging paired lamps on the assumption that the matching lamp on the other side is also fitted with the same replacement. Section S6.7.2 permits a replacement to be evaluated against an earlier version of the standard, which is how a lamp for a 2005 vehicle can still be compliant in 2026.

These clauses are the reason a lamp can be correctly marked and still produce a non-compliant vehicle. Section S6.7.1.2 asks a question about the finished truck, and no component marking answers it.

United States in service: 49 CFR 393.11 and 393.25 for trucks and trailers

The American in-service framework is set out below, and it is a performance framework rather than a marking one.

Section 393.11(a)(1) requires that a commercial motor vehicle manufactured on or after 25 December 1968 be equipped with lamps and reflective devices that meet at least the version of FMVSS No. 108 in effect at the time of manufacture. Table 1 in the same section then specifies, vehicle class by vehicle class, how many lamps of each type are required, what colour each must be, where each must be mounted and the permitted mounting height. The published ranges include headlamps at 559 mm to 1,372 mm, turn signal lamps at 381 mm to 2,108 mm, and tail and stop lamps at 381 mm to 1,829 mm.

Two provisions in 393.11 are frequently misunderstood. Section 393.11(b) requires a conspicuity system of reflex reflectors for trailers that are at least 2,032 mm wide with a gross vehicle weight rating above 4,536 kg, together with the towing vehicle in some configurations. Section 393.11(c) prohibits an amber stop lamp or an amber tail lamp on a commercial motor vehicle, which is a colour rule rather than a marking rule.

Section 393.25 supplements this for lamps other than head lamps. It requires the covered lamps to meet at least the FMVSS No. 108 version in effect at manufacture, and section 393.25(c) routes certain specific devices to named SAE documents, including SAE J586, J2261, J585, J588, J2040 and J592. Section 393.25(e) then sets the general requirement that lamps be steady burning except where a flashing function is required or permitted, and it is that exception which names the warning-light standards discussed later in this article.

Part 393 is federal in-service equipment law. It does not displace state vehicle codes, and this article does not attempt to summarise any state rule, because individual states set their own requirements for use on their roads.

Warning lamps: the SAE J845 family under 393.25(e)

Section 393.25(e) names SAE J845, SAE J595 and SAE J1318 for amber warning lamps on tow trucks and oversize-load vehicles, and those references are the American route to a warning-light claim.

Standard named in 393.25(e)	Applied to	Version referenced in the current text
SAE J845	Amber warning lamps on tow trucks and oversize-load vehicles	May 1997, Optical Warning Devices for Authorized Emergency, Maintenance and Service Vehicles
SAE J595	Amber flashing warning lamps	January 2005
SAE J1318	Amber gaseous discharge warning lamps	May 1998

The version dates matter more than they appear to. A specification that claims J845 conformance without a version tells a buyer nothing about which test regime was applied, because the regulation text pins a specific edition. A supplier who lists the edition is describing a testable claim; a supplier who omits it is describing a family of documents that have changed repeatedly since 1997.

There is a second layer to the warning-light story that is often quoted out of context. In its 1997 notice of proposed rulemaking, the Federal Highway Administration described the three documents as they then stood, titling them “Flashing Warning Lamps” (January 1990), “360 Degree Warning Lamp for Authorized Emergency, Maintenance and Service Vehicles” (March 1992), and “Gaseous Discharge Warning Lamp” (April 1986). The same notice described a three-level class structure, Class 1, Class 2 and Class 3, and proposed that only Class 2 and Class 3 devices be permitted under the exception, with Class 1 reserved for emergency vehicles.

That class reasoning is the agency’s stated rationale in a proposal, not an operative sentence in the current regulation, and the current text of 393.25(e) does not assign classes. A supplier who claims “Class 1” performance should expect the buyer to ask which edition of which document defines that class, and to see the test report that places the product in it. For an LED warning light sold into the American market, the documentation that answers the claim is therefore the recognised edition of SAE J845, J595 or J1318, plus a test report from a laboratory that names the product. None of those documents is a government approval, and none of them creates an approval number.

UN type approval: how an E-mark is actually granted under UN R148

The E-mark belongs to a different legal machine. UN Regulation No 148, published in the Official Journal of the European Union at L 347/123 on 30 September 2021 as document 2021/1719, consolidates a set of earlier lighting regulations, and its approval procedure is what produces the marking.

The regulation merges UN Regulations No 4, 6, 7, 23, 38, 50, 77, 87 and 91 into one text. Its scope covers light-signalling devices including the licence plate lamp, direction indicator lamps, position lamps, stop lamps, end-outline marker lamps, reversing lamps, the manoeuvring lamp, the rear fog lamp, parking lamps, daytime running lamps and side marker lamps. For a supplier of LED auxiliary lighting, the presence of the daytime running lamp in that list is the reason a DRL function can be type approved at all.

Section 3 of R148 sets out who applies and what they submit. The applicant is the holder of the trade mark for the lamp, and the application is filed with the approval authority of a Contracting Party, with drawings and technical descriptions sufficient to identify the lamp type, including the space reserved for the approval marking or for the Unique Identifier and the identification code space for an LED module where one is used.

The record of the decision is Annex 1 to the regulation, the communication form. That form carries the approval, extension, refusal or withdrawal, the lamp category, the change index, the approval number, the Unique Identifier, the technical service that tested the lamp and the test report number, and a footnote to the form requires the distinguishing number of the country that granted the approval to be shown. This is the document a buyer should ask for by name, because it is the only artefact that ties a marking on a lens to an authority, a test and a product. Two consequences of the model follow: an approval is granted to a type, so a certificate is only relevant if the product identification matches, and the approving authority belongs to one country, which is why the mark carries a country number rather than a global one. An E4 marking is evidence about a Dutch approval decision, and nothing more.

How to decode an E-mark: country number, approval number, regulation and series

An E-mark is a compact record. Every field in it has a defined meaning, and a buyer who can read the fields can tell which authority acted, on what basis, for which function, and with what installation constraint.

The circle or rectangle comes first. UN R148 Annex 7 shows the approval marking as a circle containing the letter E, followed by the distinguishing number of the country that granted the approval, then the approval number, then the regulation code with its series of amendments, then the function letters. The letter E inside a circle belongs to the UN type approval system. Where a document or a lens shows a lower-case e inside a rectangle, that is a different mark belonging to the European Union’s own type approval framework, discussed further below.

Field in the marking	Example from R148 Annex 7	What it means
Circle with E	E4	A UN type approval granted in the Contracting Party whose distinguishing number is 4
Approval number	221, 3223, 3333, 1432, 17325	The serial number the authority assigned to that approval
Regulation code	148R	The approval was granted under UN Regulation No 148
Series of amendments	00 after the regulation code	The device was approved to the original series of amendments rather than to a later one
Function letters	A, F3, PL	The specific functions and material characteristics covered by the approval
Unique Identifier	An alphanumeric string	An alternative to the marking, held in the UNECE database

The series number is the field buyers misread most often. The two digits after the regulation code identify which series of amendments to the regulation the approval was granted under, so an 00 entry records an approval to the original series. A later series of amendments would be recorded with a different number, and the difference is substantive: it identifies which version of the technical requirements was applied when the device was tested. A device approved under two regulations, such as 148R for light-signalling devices and 149R for road illumination devices, shows both codes. An arrow elsewhere in the marking states the installation orientation that satisfies the photometric requirement, and a downward-pointing arrow indicates a restricted light distribution.

The function letters are the field that turns a mark into a specification. In R148 Annex 7 the examples include A for a front position lamp, F3 for a front fog lamp, PL for a plastic lens, 1A for a class 1A retro reflector, 2b for a rear direction indicator lamp with variable intensity, R2 for a rear position lamp with variable intensity, F2 for a rear fog lamp with variable intensity, AR for a reversing lamp, and S2 for a stop lamp with variable intensity. The same annex supplies the worked examples below, each of which is a reading of the annex itself and not a description of a product on the market.

Worked example in R148 Annex 7	Country and approval number	Regulations shown	Functions and characteristics
Front position lamp	E4, approval 221	148R, series 00	A
Front position lamp plus front fog lamp	E2, approval 3223	148R and 149R	A, F3, PL for a plastic lens
Compound rear lamp	E4, approval 3333	148R	1A, 2b, R2, F2, AR, S2
Reused lamp lens	E9, approval 1432	As approved for the lamp	Lens must carry the unique valid approval marking
Light source module	E3, approval 17325	Module identification code	Module identification code, approved with the lamp

Read as sentences, the examples show what a mark can and cannot tell you. The E4 approval number 221 under 148R series 00 says that the Dutch authority granted a numbered approval under the consolidated light-signalling regulation at its original series of amendments, and that the function covered is A. The E2 approval number 3223 carries two regulation codes, 148R and 149R, which means separate approvals for light-signalling and road illumination devices, while the letters PL declare a plastic lens and not a function. The E4 approval number 3333 covers six functions on one rear lamp assembly. The E9 approval number 1432 concerns a reused lamp lens and requires the lens to carry the unique valid approval marking, with a light source module approved together with the lamp under its own identification code, which the Italian E3 approval number 17325 illustrates.

Two boundaries apply to this material. UN Regulation No 149 appears only because Annex 7 shows the code 149R; its scope and effective dates were not obtained from a primary text, and the same caution applies to UN Regulation No 150. And the examples illustrate the structure of a marking rather than a list of approved products.

The country number is the field most often asked about and least often answerable in full. Annex 7 of R148 gives worked examples that identify four distinguishing numbers: E2 for France, E3 for Italy, E4 for the Netherlands and E9 for Spain. Beyond those four, this article does not publish a list, because the complete table of distinguishing numbers assigned under the 1958 Agreement was not obtained from a primary source, so the Annex 1 communication form is the document to request for an unfamiliar number.

One structural exception applies to the whole marking. R148 states in its introduction that where the Unique Identifier is used, the lamp is not required to carry the conventional approval marking, and where use of the Unique Identifier is not technically possible, the conventional marking must be used. The Unique Identifier is held in the UNECE secure database established under the 1958 Agreement. A lens with a long alphanumeric string instead of a circle and a number is therefore not an unmarked lens; it is a lens using a different recording route.

The EU layer: 2019/2144 and the e mark under 2018/858 Article 38

Regulation (EU) 2019/2144, adopted on 27 November 2019 and published in the Official Journal on 16 December 2019, handles the first job. Article 4(2) provides that type approvals granted under the UN regulations listed in Annex I are considered EU type approvals. Article 4(5) requires vehicles, systems, components and separate technical units to comply with the requirements listed in Annex II. The lighting rows in Annex II are the ones that matter for a lamp buyer, and they are grouped by function rather than by product.

Annex II row in Regulation (EU) 2019/2144	Subject	UN regulations listed
D11	Light-signalling devices	R4, R6, R7, R19, R23, R38, R77, R87, R91
D12	Road illumination devices	R31, R98, R112, R119, R123
D13	Retro-reflecting devices	R3, R104
D14	Light sources	R37, R99, R128
D15	Installation of lighting and light-signalling devices	R48
D2	Electromagnetic compatibility	R10
D17	Headlamp cleaning	R45

Two structural facts follow from that table. First, the list of light-signalling regulations in row D11 is the pre-consolidation list, which is why UN Regulation No 148, the consolidation of those nine regulations, becomes the operative component text for new approvals. Second, the installation of lighting is a separate row, D15, pointing at UN Regulation No 48. Component approval and installation approval are separate legal acts in the European Union, exactly as they are in the United States.

Regulation (EU) 2018/858 handles the second job, the marking of parts. Article 38(2) requires manufacturers of components or separate technical units to affix the type approval mark required by the relevant regulatory act listed in Annex II, and where no such marking requirement exists, the same paragraph requires at least the manufacturer’s trade name or trade mark and the type number or identification number. Article 38(3) provides that the model of the EU type approval mark is set by implementing acts, with the first such act to be adopted by 5 July 2020, and Article 38(4) restricts economic operators to placing on the market only products marked in accordance with the regulation.

The difference between the two marks is the practical point of any DOT vs E-mark comparison. The E in a circle records an approval granted under a UN regulation by a national authority of a Contracting Party, while the e in a rectangle belongs to the European Union’s own type approval system for components and separate technical units, so the two do not describe the same legal act. The model and appearance of the EU type approval mark are set out in implementing acts, and the specific implementing act number and its figure were not obtained for this article.

The reader now has both halves of a DOT vs E-mark reading, and the comparison section that follows places the marks side by side.

DOT vs E vs e: a claim-by-claim comparison

The comparison below places the three marks side by side on the dimensions that decide a purchase, and it is a reading of the regulatory texts already cited rather than a statement about any particular product.

Dimension	DOT	E in a circle	e in a rectangle
Legal system	United States federal	UN 1958 Agreement	European Union
Governing text	49 CFR 571.108 S6.5.1 and S6.5.1.2, 49 U.S.C. 30115	UN Regulation No 148	Regulation (EU) 2018/858 Article 38
Who issues the claim	The manufacturer or distributor	The approval authority of a Contracting Party	The EU approval authority
Is there an approval number	No	Yes, recorded in the Annex 1 communication form	Yes, under the EU type approval framework
Is the mark mandatory	On headlamps and beam contributors	For the approved device type under the regulation	For components and separate technical units subject to a marking requirement
What the mark covers	The item’s conformance to FMVSS No. 108	The approved functions, lens material and installation constraints	The component or separate technical unit as an approved type
How a buyer verifies it	Request the certification statement and the test file	Request the approval number and the Annex 1 form	Request the EU type approval reference
What it does not cover	Installation, state rules, use	Installation under R48, national road rules	Installation, national road rules
Where EMC approval sits	Not applicable to this mark	Not applicable to this mark	Not applicable to this mark
Scope of the claim	A marking that is compulsory on headlamps and optional elsewhere, and that says nothing by itself about construction	A device type that was examined before it was placed on the market	An approved component or separate technical unit

The last row is deliberate. Electromagnetic compatibility is a separate approval track in the European Union under UN Regulation No 10, and it appears in Regulation (EU) 2019/2144 Annex II as row D2. A lamp can hold a lighting approval without holding an EMC approval, and an EMC approval says nothing about optical performance. The site’s earlier article on UN R10 vs CISPR 25: Vehicle Lighting EMC Explained covers the EMC track in detail, including why an EMC approval is not a statement about road use.

What an approved component does not prove on your vehicle

The gap between a component approval and a lawful installation is not a technicality. It is written into every one of the five systems covered here.

In the United States, S6.2.1 of 49 CFR 571.108 prohibits installing any additional lamp, reflective device or other motor vehicle equipment that impairs the effectiveness of lighting equipment the standard requires. Section S6.7.1.2 requires that a replacement lamp, once installed, not take the vehicle out of compliance with the standard. Section 393.11 Table 1 then imposes position, height, count and colour requirements on commercial motor vehicles in service that a component certificate does not address at all. In the UN and European Union system, installation is a regulation in its own right: UN Regulation No 48 is listed separately in Regulation (EU) 2019/2144 Annex II as row D15, and 49 CFR 571.5 incorporates UNECE Regulation 48 in full into section 571.108, which is how the American standard reaches installation questions as well. A lamp type approval granted under R148 does not carry an R48 installation approval with it.

In Australia, the Australian Design Rule 13/00 is built on the UN Regulation No 48 appendix, which keeps the installation layer explicit even in a self-certification regime. Canada takes the opposite route and reproduces the American standard, so installation logic travels with CMVSS 108 and Technical Standards Document 108 rather than with a separate installation regulation. The United Kingdom applies its own lighting regulations and then checks the result at the annual test.

The operational conclusion is blunt. An approved lamp placed in the wrong position, at the wrong height, in the wrong quantity, or wired to the wrong circuit produces a non-compliant vehicle even though every certificate is genuine, and whether that vehicle may then be driven where you live depends on the law of that place, which is the subject of Are LED Light Bars Street Legal?. Once the installation question is settled, the remaining practical issue is aiming and glare control, covered in Auxiliary Light Aiming and Glare: A Practical Safety Guide.

Daytime running lamps: the approval path, the DRL label and the MOT rule

A daytime running lamp is a good test case for the whole subject, because it carries its own mandatory label in the United States and its own inspection rule in the United Kingdom.

Under 49 CFR 571.108, S6.5.2 requires a lamp used as a daytime running lamp, where it is not optically combined with a headlamp, to be permanently marked on the lens with the letters DRL at a character height of at least 3 mm. Section S6.5.1.2 still governs whether that lamp may also carry a DOT symbol, and the answer remains the same: it may, and it is not required to. Section S6.1.1.4 sets the wiring conditions under which the function is permitted.

Under UN Regulation No 148, the daytime running lamp is inside the scope of the consolidated regulation along with the licence plate lamp, direction indicators, position lamps, stop lamps, end-outline marker lamps, reversing lamps, the manoeuvring lamp, the rear fog lamp, parking lamps and side marker lamps, which is why a DRL function in the European market is described by a type approval rather than by a self-declaration.

The United Kingdom takes a narrower inspection position. The DVSA MOT inspection manual for cars and passenger vehicles inspects daytime running lamps only where they were fitted as original equipment to an M1 vehicle first used on or after 1 March 2018, and it applies two checks: not more than two daytime running lamps, and white light. The manual also records that the lamps may switch off when the direction indicator on the same side is operating, which is a functional allowance rather than a defect route.

One warning belongs here for anyone considering an aftermarket daytime running light on a European vehicle. The fact that a lamp carries a DRL label or an E mark does not make an added DRL compliant, because the number of lamps and their switching logic are installation matters. In the Australian rule set, for example, an illuminated badge exemption is limited to a luminous intensity of not more than 60 candelas, must not flash, must sit more than 200 mm from the nearest lamp, and may only be lit together with the front position lamps. Canada takes a third route and reproduces the American standard instead of a UN regulation, which is why a daytime running lamp sold into Canada is described by the same clauses as one sold into the United States, subject to the Canadian deviations noted below.

Reflex reflectors, conspicuity and “reflective tape”

Reflectors are the part of the lighting system where buyers most often substitute one artefact for another, and the rules are unusually specific about the difference.

In the United States, section 571.108 S6.1.1.1 requires a reflex reflector conspicuity system on trailers that are at least 2,032 mm wide with a gross vehicle weight rating above 4,536 kg, and on the towing vehicle in the covered configurations. In service, 49 CFR 393.11(b) restates that requirement for commercial motor vehicles, tying the system to the same width and weight figures. A conspicuity system built from reflex reflectors is a required equipment item, not decoration.

The United Kingdom states the substitution rule directly. The DVSA MOT inspection manual records that reflective tape cannot be used in place of a rear reflector. A strip of retro-reflective material, however bright, is not accepted as satisfying the reflector requirement at the annual test. In the European Union, retro-reflecting devices are listed in Regulation (EU) 2019/2144 Annex II as row D13, pointing at UN R3 and R104.

The colour rules that sit alongside the reflector requirements are also stricter than most buyers expect. Section S6.1.2 of 49 CFR 571.108 treats amber and yellow as the same colour, and 49 CFR 393.11(c) prohibits amber stop lamps and amber tail lamps on commercial motor vehicles. A reflector or lamp that changes the colour of a required function is a compliance problem even when the added item is individually well made.

License plate lamps: a small lamp with explicit rules

The licence plate lamp is the smallest lamp in the set and one of the most tightly specified, which makes it a useful check on any claim that a lighting rule is vague.

Section 571.108 S6.1.3.3 addresses the licence plate lamp in the American standard, and 49 CFR 393.11 carries a footnote for it in the in-service table for commercial motor vehicles. The United Kingdom states the functional rule in the MOT inspection manual: the licence plate lamp must be lit at the same time as the position lamps, and it must not project white light directly rearwards. That is a switching requirement and an optical requirement in one sentence.

Jurisdiction	Rule	Operative reference
United States	A required lamp with its own clause in the standard, and a footnote in the in-service table	49 CFR 571.108 S6.1.3.3 and 49 CFR 393.11, footnote 11
United Kingdom	Must be lit with the position lamps; must not project white light directly rearwards	DVSA MOT inspection manual, section 4.7
UN and European Union	Licence plate lamp inside the scope of the consolidated light-signalling regulation	UN Regulation No 148

The licence plate lamp also illustrates a general principle of this article. Section S6.1.3.1 of the American standard requires lamps to be mounted on a rigid part of the vehicle, and section S6.1.3.6 sets spacing requirements between auxiliary lamps and identification lamps, so no approval mark on the lamp can satisfy the rules about where it sits.

Trailers, trucks and fleets: what changes with vehicle class

A fleet buyer faces a different question from a private buyer, because the same lamp is judged against a different instrument depending on the vehicle it is fitted to and the date that vehicle was built. For a commercial motor vehicle in the United States, 49 CFR 393.11(a)(1) sets the benchmark as the version of FMVSS No. 108 in force when the vehicle was manufactured, for vehicles built on or after 25 December 1968. Table 1 in the same section then specifies lamp counts, colours, positions and heights by vehicle class, and section 393.11(b) adds the conspicuity requirement for trailers at or above 2,032 mm in width with a gross vehicle weight rating above 4,536 kg. Section 393.25(c) routes specific devices to named SAE documents, and section 393.25(e) names the warning-light standards. For a trailer sold into Europe, the component route runs through UN Regulation No 148 for the lamps and UN Regulation No 48 for the installation, with Regulation (EU) 2019/2144 Annex II listing both. In Australia, ADR 13/00 covers installation for vehicles other than L-group vehicles and permits up to four additional driving lamps under clause 8.1.6, provided the conditions in clause 9.3 are met.

Fleet question	United States	UN and European Union	Australia
Component benchmark	FMVSS No. 108 as in force at manufacture for in-service CMVs	UN Regulation No 148 for light-signalling devices	ADR 13/00 clause 6.1, using the modified UN R48 appendix or a clause 11 alternative
Installation benchmark	49 CFR 393.11 Table 1 with position, height, count and colour rules	UN Regulation No 48	ADR 13/00, with Table 1 per lamp function
Additional driving lamps	Permitted only if they do not impair required lighting, under S6.2.1	Installation rules under R48 apply	Up to four under clause 8.1.6, subject to clause 9.3
Warning lamps	SAE J845, J595, J1318 named in 393.25(e)	UN Regulation No 65 for special warning lamps	ADR 13/00 Table 1, with the ADR mapping to UN regulations

A fleet specification should therefore name the vehicle class and the year of manufacture, not just the lamp part number, because the vehicle class in Table 1 and the lamp certificate come from different rules.

Canada: CMVSS 108 as a reproduction of TSD 108

Canada imports another country’s technical text rather than writing its own. Transport Canada’s consultation page on updated requirements for Technical Standards Document 108 states that the Canadian Motor Vehicle Safety Standard 108, Lighting System and Retroreflective Devices, sets out the requirements for lamps and reflective devices on road vehicles, and incorporates Technical Standards Document (TSD) 108, Lamps, Reflective Devices, and Associated Equipment. The same page states that TSD 108 is a reproduction of the United States National Highway Traffic Safety Administration lighting standard, and it links directly to 49 CFR 571.108, while the Motor Vehicle Safety Act requires manufacturers and importers to self-certify that their vehicles and equipment comply with the safety regulations.

Two consequences follow. A lamp intended for the Canadian market is judged against a text that is, in substance, the American standard, which is why the DOT logic and the SAE incorporation described above apply there as well, and self-certification again puts the evidence burden on the manufacturer or importer rather than on a pre-market approval.

Canada also illustrates that a reproduction is not an exact copy. Transport Canada’s consultation, which ran from 4 October 2024 to 3 December 2024, records that the current Canadian requirement for school bus signal lamps is four mandatory red lamps, two at the front and two at the rear, plus four optional amber lamps, and that the proposal under consultation would move to a mandatory eight-lamp system with the amber lamps becoming mandatory. One limit on this section should be explicit: the internal clause numbering of TSD 108 Revision 8 was not obtained, because the document is distributed as a PDF that could not be retrieved for this article, so any statement about a specific Canadian paragraph number should be checked against the official text.

United Kingdom: the equivalent standards route and the MOT test

The United Kingdom runs two things side by side: a regulation that allows equivalent standards, and an annual inspection that tests the result.

The Road Vehicles Lighting Regulations 1989, made in 1989 and in force from 1 November 1989, contain the route. Regulation 3A, inserted by SI 1994/2280 with effect from 1 October 1994, permits a corresponding standard to be used in place of the British Standard. A corresponding standard may be a national standard of a country in the European Economic Area, an international standard, or a technical specification or code of practice recognised by a public authority. The condition is substantive: the corresponding standard must provide a level of safety equivalent to that of the British Standard, and it must contain marking requirements equivalent to those in the relevant instrument, which links back to regulation 3(6) on the application of British Standard markings.

Regulation 4 does two further jobs. Paragraph 4(3) provides that between sunrise and sunset certain classes of vehicle are not required to be fitted with lamps or reflectors at all. Paragraph 4(4) provides that a lamp which is obscured, covered or not connected is not treated as a lamp for the purposes of the regulations. Both provisions matter to anyone reading a marking: a lamp that is physically present but covered is, in the eyes of the regulations, not there.

The MOT inspection manual, published by the Driver and Vehicle Standards Agency, then sets out what an examiner actually tests. The sections relevant to markings and lamps include the following points.

MOT check	What the manual states	Section reference
Side direction indicator lens	Accepts a wraparound lens marked either with an E mark in a circle or an e mark in a rectangle with the number 5 above it, which shows both marking families in one inspection regime	4.4.1
Headlamp identity	A high intensity discharge headlamp can be identified by a DCR marking on the lens or the lamp body	4.1.4, 4.1.5, 4.1.6
Halogen headlamps first used from 1 April 1986	Must not be converted to a high intensity discharge or LED light source; the defect recorded is that the light source and lamp are not compatible	4.1
Replacement of a complete lamp	Replacing the whole lamp with one that already contains a high intensity discharge or LED light source is not a defect on that ground, and the lamp is checked to the requirements for its type	4.1
Direction indicator flash rate	Between 60 and 120 flashes per minute	4
Rear reflector and licence plate lamp	Reflective tape cannot be used instead of a rear reflector; the licence plate lamp must be lit with the position lamps and must not project white light directly rearwards	4.8 and 4.7

Two limits apply to this section: the specific implementing act that models the European Union’s e type approval mark, and its published figure, were not obtained, and the manual’s reference to the number 5 above the e mark is quoted as a description used by the manual rather than as a complete decoding of the mark.

Australia: ADR 13/00, self-certification and the excluded UN annexes

Australia is the most instructive of the three non-American systems, because it states outright which parts of the UN regulation it declines to adopt.

The Vehicle Standard (Australian Design Rule 13/00 – Installation of Lighting and Light Signalling Devices on other than L-Group Vehicles) 2005, in Compilation No. 8 with a compilation date of 1 October 2023, sets the framework. Clause 6.1 requires a vehicle to comply either with Appendix A as varied by Parts 7, 8, 9 and 10 of the rule, or with one of the alternative standards in clause 11. Clause 7.1 then excludes a defined set of UN Regulation No 48 provisions from the Australian application: the scope, the application for approval, the approval itself, changes to approvals, penalties for non-conformity of production, production definitely discontinued, the list of technical services, and the transitional provisions. It also excludes Annex 1, the communication form, Annex 2, the arrangement of the approval mark, and Annex 9. Australia keeps the technical content and discards the approval machinery, so a lamp sold into Australia does not carry an Australian approval number derived from R48.

Element of ADR 13/00	Content	Clause
Compliance route	Appendix A as varied by Parts 7 to 10, or an alternative standard under clause 11	6.1
Excluded UN R48 provisions	Scope, application for approval, approval, changes to approvals, penalties, production non-conformity, discontinued production, technical services list, transitional provisions	7.1
Excluded annexes	Annex 1 the communication form, Annex 2 the approval marking arrangement, Annex 9	7.1
Illuminated badge exemption	Eight conditions, including an integrated light source and badge, white light at the front, amber at the sides, red at the rear, not more than 60 candelas, no flashing, more than 200 mm from the nearest lamp, and illumination only with the front position lamps	7.6
Additional driving lamps	Up to four, subject to clause 9.3	8.1.6

The mapping in Table 1 links UN provisions and regulations to equivalent Australian Design Rules, including UN R112 and R98 to ADR 46/00 and ADR 77/00, UN R7 to ADR 49/00, UN R23 to ADR 1/00, UN R6 to ADR 6/00, and UN R87 to ADR 76/00, while R48 itself is applied through the several ADRs rather than as a standalone approval. The illuminated badge exemption in clause 7.6 shows how precisely a modern lighting rule has to be written: a badge that contains its own light source may be illuminated only if all eight conditions are met, including a luminous intensity of not more than 60 candelas, no flashing, a separation of more than 200 mm from the nearest lamp, a colour that is white at the front, amber at the sides and red at the rear, illumination only while the front position lamps are on, and no interference with the driver’s view.

A ten-step procedure for reading a lamp before you buy

The procedure below applies the clauses cited in this article in the order a buyer meets them, and it requires the product, the packaging and the supplier’s answer to a written question.

• Read the lens for the symbol DOT and note whether the device is a headlamp, a beam contributor or a replaceable headlamp lens. Only those categories require the symbol under 49 CFR 571.108 S6.5.1.
• Read the rest of the headlamp data set if the device is a headlamp: the registered trademark under S6.5.3.1, the voltage and model or trade number under S6.5.3.2, and the HB type or discharge source design number under S6.5.3.4.1 where the light source is replaceable.
• Look for the letters DRL at a character height of at least 3 mm if the lamp is intended to function as a daytime running lamp that is not optically combined with a headlamp, as required by S6.5.2.
• Look for the words “sealed beam” and the identification code at a character height of at least 6.35 mm if the lamp is a sealed beam unit, as required by S6.5.3.3.1.
• If there is a circle containing E, record the country number, the approval number, the regulation code, the series digits and every function letter, and compare each field with the definitions in UN Regulation No 148 Annex 7.
• If there is an alphanumeric string instead of the conventional marking, ask the supplier whether a Unique Identifier is in use, because R148 does not require the conventional marking in that case.
• Ask for the Annex 1 communication form that corresponds to the approval number on the lens, and check the applicant name, the lamp category, the change index and the granting authority.
• If the lens or the datasheet shows an SAE code, identify which incorporated document the code points to under 49 CFR 571.5, and ask for the test report that applies that document to the product.
• Ask one written question: which vehicle class, which position, which mounting height and which wiring does this lamp satisfy, and under which clause. The answer is the installation evidence, and no lens marking replaces it.
• Verify that the lamp you are buying is the type named in the certificate, and that the certificate covers the function, the lens material and the light source you intend to use.

The procedure deliberately ends on installation and identification, because that is where most purchases fail: a lamp that passes steps 1 to 9 can still be placed at the wrong height, in the wrong quantity or on the wrong circuit, or be a variant that the certificate does not name.

Documents to request from a supplier, and what each one proves

A written request with five named documents separates a supplier that holds evidence from one that holds a slogan.

Document to request	What it proves	What it does not prove
Certification statement for FMVSS No. 108, naming the product	That the manufacturer has certified conformance under 49 U.S.C. 30115	That any agency reviewed or approved the product
Test report against the applicable SAE document and edition	That a laboratory tested the product against the named edition, such as SAE J845 May 1997 or SAE J575	That the installation on your vehicle satisfies 49 CFR 393.11 Table 1
UN type approval certificate or the Annex 1 communication form	That an authority granted a numbered approval for a named lamp type, with a technical service and report number	That it covers a different product identification or function
EU type approval reference under Regulation (EU) 2018/858 Article 38	That the component or separate technical unit carries the required marking	That national road rules permit its use
Declaration of conformity with the relevant ADR or CMVSS requirement where self-certification applies	That the responsible exporter has certified compliance in that market	That a government body issued an approval number

Two of the products on this site, the Hornet TL LED Warning Light (Amber/Red/Blue) | R65 & J845 Certified and the Surfboard Mini LED Warning Light (Amber/Red/Blue) | R65 & J845 Certified, are listed with an R65 and J845 claim, which is a manufacturer statement rather than evidence that a third party has verified the products, and this article does not confirm it. The two references also describe different systems: J845 is the SAE document named in 49 CFR 393.25(e) for amber warning lamps, while R65 is a UN type approval regulation whose formal title is “Uniform provisions concerning the approval of special warning lamps for power-driven vehicles and their trailers”, in force since 15 June 1986 and open to 39 Contracting Parties according to the United Nations Treaty Collection status page. A fleet buyer should request the J845 test report with its edition date, and the R65 approval number with its granting authority and certificate. The full range is listed under LED Warning Lights and alongside work lights in the Industrial range.

Red flags in lighting claims

Five phrases recur in listings and datasheets, and each one can be replaced with a verifiable question.

Claim as written	The problem	What to ask instead
DOT approved	There is no federal approval for lighting equipment; the mark is a manufacturer certification under 49 U.S.C. 30115	Which entity certified conformance to FMVSS No. 108, and can you send the certification statement for this part number
E-mark certified	A granted approval belongs to a country, a number and a lamp type, so the phrase omits everything that makes it checkable	What is the approval number, which authority granted it, and can you send the Annex 1 communication form
SAE certified without an edition	Incorporation by reference pins specific editions, such as SAE J595 January 2005 in 49 CFR 393.25(e)	Which edition of which SAE document, and can you send the test report
R65 and J845 certified	The two references belong to different legal systems, and a product page is not a certificate	What is the R65 approval number, and which laboratory tested the product to J845
Street legal	Legality depends on the vehicle, the installation and the jurisdiction, and federal law sets manufacturing and in-service equipment standards only	Which clause of which rule covers my vehicle class, position and use, and which local rule applies where I drive

The last row matters most to a consumer. A truthful supplier will separate the statement “this lamp is certified” from the statement “this lamp is legal on your vehicle”, because the second statement depends on facts the supplier does not control. Any DOT vs E-mark claim that stops at the mark answers only half of the question, and the site’s article on Are LED Light Bars Street Legal? deals with the other half, including why state rules differ.

Frequently asked questions

Does a DOT mark mean the government approved the light

No. The DOT symbol on a headlamp lens is a certification by the manufacturer under 49 U.S.C. 30115 that the item conforms to FMVSS No. 108. Section 571.108 S6.5.1 requires the symbol on headlamps and beam contributors, and section S6.5.1.2 makes it optional on other lamps while confirming that the marking, when present, constitutes the same certification. No federal body issues an approval number for a lighting component.

Is a DOT vs E-mark comparison a choice between two equivalent certifications

No. The two marks record different legal acts. A DOT symbol records a self-certification by the party placing the product on the market, while a UN E mark records a type approval granted by a national authority to the holder of the trade mark, with an approval number that appears in the authority’s communication form under UN Regulation No 148 Annex 1. One is a statement by the seller, the other is a decision by an authority, and each one covers a different scope.

Are E-mark lights legal in the United States

An E or e marking is not a United States approval, because the United States does not operate a lighting type approval system for vehicles under 49 CFR 571.108. A lamp carrying an E-mark can still be sold and used in the United States if it conforms to the applicable federal standard, but the E-mark itself does not demonstrate that conformance, and it says nothing about state or local rules on use.

Which SAE documents apply to amber warning lights in the United States

49 CFR 393.25(e) names SAE J845 for amber warning lamps on tow trucks and oversize-load vehicles, SAE J595 for amber flashing warning lamps, and SAE J1318 for amber gaseous discharge warning lamps, in the editions May 1997, January 2005 and May 1998 respectively. The equivalent UN instrument is Regulation No 65, whose technical clauses were not obtained for this article and should be checked in the certificate or the standard text.

Why does the UK MOT manual mention both an E mark and an e mark

Because British inspection practice accepts either family of marking on the parts it checks. The manual’s side direction indicator example describes a wraparound lens marked with an E mark in a circle or an e mark in a rectangle with the number 5 above it. The regulation behind the equivalent standards route is regulation 3A of the Road Vehicles Lighting Regulations 1989, which allows a corresponding standard where it provides equivalent safety and equivalent marking requirements.

What should a fleet buyer ask for first

The vehicle class and model year, because those two facts decide which instrument applies. For a commercial motor vehicle in the United States, 49 CFR 393.11(a)(1) sets the benchmark as the version of FMVSS No. 108 in force at manufacture for vehicles built on or after 25 December 1968, and Table 1 in the same section sets the count, colour, position and height rules. Requesting a component certificate before establishing the vehicle class inverts the order of the analysis.

Editorial note

Written by SAEC Lighting Engineering Team, Foshan.

Last updated: 2026-10-14

This article quotes regulation text and official agency guidance only, and it does not evaluate any product for legal use on a public road. Where a primary text could not be obtained, the article says so and does not fill the gap: the technical clauses of UN Regulation No 65, the full tables of SAE J845, J595, J1318 and J759, the complete list of E-mark country distinguishing numbers, the clause numbering of Transport Canada Technical Standards Document 108 Revision 8, the details of UN Regulations No 149 and No 150, and the content of the pending 9 September 2026 amendment cross-reference to 49 CFR 571.5 were all unavailable at the time of writing. Claims printed on product pages, including R65 and J845 claims, are treated as manufacturer statements and require certificates to substantiate. Anyone making a decision about a specific vehicle should confirm the current text with the issuing authority and the rules of the jurisdiction where the vehicle is used.

Sources

• eCFR, 49 CFR 571.108 Standard No. 108; Lamps, reflective devices, and associated equipment: https://www.ecfr.gov/current/title-49/subtitle-B/chapter-V/part-571/subpart-B/section-571.108
• eCFR, 49 CFR 571.5 Matter incorporated by reference: https://www.ecfr.gov/current/title-49/subtitle-B/chapter-V/part-571/subpart-A/section-571.5
• eCFR, 49 CFR 393.11 Lamps and reflective devices: https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-393/subpart-B/section-393.11
• eCFR, 49 CFR 393.25 Requirements for lamps other than head lamps: https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-393/subpart-B/section-393.25
• govinfo, 49 U.S.C. 30115 Certification of compliance, United States Code 2023 Edition: https://www.govinfo.gov/content/pkg/USCODE-2023-title49/html/USCODE-2023-title49-subtitleVI-partA-chap301-subchapII-sec30115.htm
• govinfo, Federal Register Vol. 62 No. 71, 14 April 1997, FHWA notice of proposed rulemaking, 62 FR 18170: https://www.govinfo.gov/content/pkg/FR-1997-04-14/html/97-9056.htm
• GOV.UK, MOT inspection manual: cars and passenger vehicles, 4. Lamps, reflectors and electrical equipment: https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/4-lamps-reflectors-and-electrical-equipment
• legislation.gov.uk, The Road Vehicles Lighting Regulations 1989, regulation 3A: https://www.legislation.gov.uk/uksi/1989/1796/regulation/3A
• legislation.gov.uk, The Road Vehicles Lighting Regulations 1989, regulation 4: https://www.legislation.gov.uk/uksi/1989/1796/regulation/4
• legislation.gov.au, Vehicle Standard (Australian Design Rule 13/00) 2005, Compilation No. 8: https://www.legislation.gov.au/F2005L03991/2023-10-01/2023-10-01/text/original/epub/OEBPS/document_1/document_1.html
• EUR-Lex, UN Regulation No 148 [2021/1719], OJ L 347/123: https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:42021X1719
• EUR-Lex, Regulation (EU) 2019/2144, OJ L 325/1: https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32019R2144
• EUR-Lex, Regulation (EU) 2018/858, OJ L 151/1: https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32018R0858
• Transport Canada, Updated requirements for Technical Standards Document 108: https://tc.canada.ca/en/corporate-services/consultations/updated-requirements-technical-standards-document-108
• United Nations Treaty Collection, Chapter XI.B.16.65, United Nations Regulation No. 65, status page: https://treaties.un.org/Pages/ViewDetails.aspx?src=TREATY&mtdsg_no=XI-B-16-65&chapter=11&clang=_en
• Cornell Law School Legal Information Institute, 49 CFR 571.108 mirror text, used to cross-check definitions: https://www.law.cornell.edu/cfr/text/49/571.108