- 1 - ICS 43.040.20 
T 38 
 
  
 
National Standard  
of the People's Republic of China 
  
GB11554 - XXXX 
 Replaces GB 11554-1998 
 
 
Photometric characteristics of rear fog lamp 
for power-driven vehicles and their trailers 
 
 
  
Draft for approval 
 
 
 Issue Date: 20XX – XX – XX Implementation Date: 20XX – XX – XX 
 
Issued by General Administration of Quality Supervision, Inspection and 
Quarantine of the People's  Republic of China and the 
 
Standardisation Administration of the  People's Republic of China (SAC) 
 
 
- 2 -  
Foreword 
 
All of the technical cont ents set out in this Standard are mandatory. 
 
This Standard corresponds to the Revision 2,  Amendment 2 of ECE R.38, “Uniform provisions 
concerning the approval of rear fog lamps for pow er-driven vehicles”. The conformance degree 
between this Standard and ECE R38 is non-e quivalent, and the main differences are: 
− Clause 1 – Scope has been modified; 
− Normative References have been added; 
− the following sections and appendix which concer ns administrative provisions in ECE R38 have 
been deleted: 2. Application for approval; 3. Approval markings; 4. Approval; 10.  Conformity of production; 11. Settlement of non-conformity of production; 12. Official end of production; 13. Names and addresses of the Technical Se rvice Department responsible for conducting 
approval tests and of the Administrative Department; 
− inspection rules have been added. 
 The main technical requirements of this Standar d, such as requirements and test methods, conform 
to ECE R.38.  This Standard replaces GB11554 – 1998, “Photometric characteristics of rear  fog lamp for motor 
vehicles and their trailers”. Compared to the prev ious version, the main changes to this Standard 
are: 
− Clause 1 of previous version – Scope – has been modified; 
− Clause 2 of previous vers ion – Normative references; 
− Clause 3 of previous version – the relevant pr ovisions in Definitions – have been modified; 
− Clause 4 of previous version – the relevant Articles in Tec hnical requirements– have been 
modified; 
− Clause 5 of previous version – Te st methods – has been modified; 
− Clause 6 of previous version – In spection rules– has been modified; 
− Articles relevant to rear f og lamps which use light source module have been added; 
− Articles relevant to rear fog lamps with  variable intensity have been added. 
 Transitional requirements for the im plementation of this Standard: rear fog lamps for power-driven 
vehicles which have newly applied for type approva l shall conform to this Standard. For rear fog 
lamps for power-driven vehicles which have passe d type approval before the implementation date 
of this Standard: if th ere is any non-conformity with the corr esponding provisions of  this Standard, 
a transitional period of 24 months shall be granted. 
 This Standard is proposed by China Nati onal Development and Reform Commission.  
 This Standard is under the jurisdiction of the National Automobile Standardisation Technical 
Committee.  - 3 - The organisation that participated in  the drafting of this Standard:  
Shanghai Automotive Lamp Research Institute.  The main drafters of this standard:  Zhou Tao, Wang Jinjun  This standard replaces the previously issued Standard: 
- GB11544-1998. 
 - 4 -            
Photometric characteristics of rear fog lamp  
for power-driven vehicl es and their trailers 
(Draft for approval) 
1 Scope 
This Standard specifies the technical requirements,  test methods and inspection rules for the rear 
fog lamps for power-driven vehicles.  This Standard applies to all t ypes of rear fog lamps for the us e of power-driven vehicles of 
categories L3, L4, L5, L7, M, N, and O.  The rear fog lamps for power-driven vehicles in this  Standard are refereed to as the rear fog lamps. 
2 Normative References 
The provisions of the following documents become  provisions of this Standard after being 
referenced. For dated reference documents, a ll later amendments (excluding corrigenda) and 
versions do not apply to this Standard; however, the parties to the agreement are encouraged to 
study whether the latest versions of these doc uments are applicable. For undated reference 
documents, the latest versions apply to this Standard.  GB 4599 Motor vehicle headlamps equipped with filament lamps  GB 4785 Prescription for installatio n of the external lighting and li ght signalling devices for motor 
vehicles and their trailers  GB 15766.1 Filament lamps for road vehicles – Di mensional, electrical and luminous requirements 
 ECE R.37 Uniform provisions concer ning the approval of filament la mps for use in approved lamp 
units of power-driven vehicl es and of their trailers 
3 Terms and definitions 
The terms and definitions specified in GB 4785 apply to this Standard. 
4 Requirements 
4.1 General provisions 
 4.1.1. The rear fog lamps shall be designed and cons tructed such that in normal use conditions, 
despite the vibrations to which they may then be subjected, they continue to function satisfactorily 
and retain the characteristics prescribed by this Standard.  4.1.2 The light source module in the re ar fog lamp, shall be designed such that the light source can 
be fitted in the correct position even in darkness; and shall be tamperproof. 
 4.1.3 When the adjustment device of the luminous in tensity for the rear fog lamp with variable 
intensity has lost its efficiency, it shall be able  to automatically meet the requirements of the 
photometric characteristics for the rear  fog lamp with mixed intensity. 
 - 5 - 4.1.4 If filament lamps are employed, the filament lamp s shall be in conformity  with the provisions 
in GB15766.1 or ECE R37. 
 
4.2 Photometric characteristic  4.2.1 Within the angle range specified below, the lu minous intensity emitted by the rear fog lamp in 
all directions shall conform to the following provisions:  4.2.1.1 From the horizontal H-H line and vertical V- V line which go thr ough the reference axis, 
within the range of between 10o to  the left and 10o to the right , and between 5o up and 5o down of 
the reference axis (See to Diagram 1), the minimu m value of the luminous intensity emitted by the 
rear fog lamp shall be 150cd;  4.2.1.2 In the diamond area of the photometric screen  in Diagram 1, by visu al inspection if any 
noticeable changes of the luminous intensity is di scovered, then apart from checking whether the H-
H line and V-V line have met the provisions men tioned above, shall also check the luminous 
intensity of the other parts within this  area, the minimum value shall be 75cd; 
 
4.2.1.3 In all light-visible directions, the maximu m value of the luminous intensity emitted by the 
rear fog lamp with mixed intensity shall be 300cd; the maximum value of the luminous intensity emitted by the rear fog lamp with variable inte nsity shall be 840cd, but shall not exceed 300cd 
when operated at night;   4.2.2 In the case of a single lamp containing more th an one light source, the lamp shall comply with 
the minimum intensity required wh en any one of the light sources  has failed. When all the light 
sources are illuminated, the maximum lumi nous intensity shall not be exceeded. 
 
4.2.3 The apparent surface in the direction of  the reference axis shall not exceed 140 cm2. 
 4.3 The light colour and its chromaticity characteris tics of the rear fog lamp  shall conform to the 
provisions in GB 4785. 
 
4.4 Heat resistance  Under the ambient temperature of 23oC ±  5oC, the rear fog lamp must be subjected to a one-hour 
test of continuous operation following a warm -up period of 20 minutes under the conditions 
specified in 5.3. After the test, th e lamp shall have no distortion, deformation, cracking or colour 
modification 
 - 6 -  
  
5 Test methods 
 
5.1 The test-darkroom, equipment and facilities shall be in conformity with the provisions in GB 
4599.  5.2 Test condition for photometric characteristics  5.2.1 In the case of the rear fog lamps equipped w ith non-replaceable light s ources (filament lamps 
or others), all the measurements shall be performed at the voltage s of 6.75v, 13.5v or 28.0v 
respectively.  5.2.2 In the case of the rear fog la mps equipped with replaceable fila ment lamps, shall use standard 
filament lamp for the rear fog lamp when tes ting, and make it work in a state which produces 
reference luminous flux. 
 
5.2.3 In the case of the rear fog lamps equipped w ith a dimmer device, under the circumstances of 
using the device correctly, the measurements shal l be performed in acco rdance with the input 
voltage specified by the manufacturer.  5.2.4 In the case of any rear fog lamps except those equipped with filament lamps, the luminous 
intensities measured after one minute and after 30 minutes of ope ration, shall comply with the 
specified values in Article 4.2. The luminous in tensity after one minute of operation can be 
calculated from the luminous intensity distribution af ter 30 minutes of operation applied at each test 
point, multiplied by the ratio of luminous intensity measured at HV after one minute and after 30 
minutes of operation.  5.2.5 The measurement of equipment f itted with multiple light sources 
 
- 7 - 5.2.5.1 When equipped with mass-produced replaceable filament lamps and operating at 6.75v, 
13.5v or 28.0v, can use the mass-produced filament lamp to perform the measurements, the  luminous intensity produ ced shall be corrected. 
The correction factor is the ratio between the 
reference luminous flux and the mean value of the luminous flux found at the voltage applied (6.75 v, 
13.5v or 28.0v), the actual luminous flux of each filament  lamp used shall not deviate more than ± 5% 
from the mean value; Alternatively a standard filament lamp may be used in turn, in each of the 
individual positions, operated at its reference flux, the individual measurements in each position being 
added together. 
 
5.2.5.2 In the case of rear fog lamps equipped with  non-replaceable light source or other light 
source, measurement shall be performed in acco rdance with the voltage specified by the 
manufacturer, when it is necessary , the manufacturer shall provide a special power supply device. 
 5.3 Test condition for heat resistance  
 
5.3.1 In the case of the rear fog lamps equipped w ith non-replaceable light s ources (filament lamps 
or others), all the measurements shall be performed at the voltage of 6.75v, 13.5v or 28.0v 
respectively.  5.3.2 In the case of the rear fog lamps equipped with  replaceable filament lamps, the test voltage 
shall enable the lamps operating in the average output power which is sp ecified in GB 15766.1 or 
ECE R.37; if in GB 15766.1 or ECE R.37, only the ma ximum power is specified, the measurements 
shall be carried out by regulating th e voltage to obtain a power equal to 90 per cent of the specified 
power.   5.3.3 For the rear fog lamps with vari able intensity, sh all enable the lamps to work at not less than 
90% of the maximum luminous intensity.  5.4 Before the test of photometric characteristics,  shall illuminate the lamp  or the rear fog lamp 
equipped with non-replaceable light s ource with the test voltage, enabli ng its light characteristics to 
be stable. 
 
5.5 The distance of measurement of the photometric ch aracteristics, shall be such that the inverse-
square law of photometry is applicable.  5.6 The angular aperture of the receiver viewed from  the reference centre of  the rear fog lamp is 
comprised between 10 angular minutes and one degree;   5.7 The angle deviation of each measur ing direction shall not exceed 15'. 
 5.8 The estimate of the measuring angle shall use the reference axis  and reference centre (indicated 
in the drawings by the manu facturer) as the datum. 
 5.9 The measurement of chromaticity shall use illu mination A light source(co lour temperature is 
2,856k).  The measurements of the rear fog lamp s using non-replaceable li ght sources shall be 
performed in accordance with the test condition specified in Secti on 5.2.1; The measurements of the 
rear fog lamps equipped with dimmer devices shall be performed with the provisions in Section 
5.2.3. Use visual observation to check  the light colour which is outside of the diamond area of 
Diagram 1, there shall not be any noticeable changes.  - 8 - 6 Inspection rules 
 
6.1  Rear fog lamps of different types for power-driven vehicles:  The lamps which differ in such essential respects as:  
a) The name and trademark of the goods; 
b) The characteristics of the opti cal system (such as the level of luminous intensity, light 
distribution angle, category of fila ment lamp, light source module,etc); 
c) The categories of the rear fog lamps (variable intensity, mixed intensity). 
 
However, a change of the colour of the filament lamp  or the colour of any light filter is regarded as 
the same type.  6.2 Type Approval  
a) 6.2.1 The types of different rear fog lamps are determined in accordance with the provisions 
mentioned in Article 6.1. 
 6.2.2 The manufacturer shall provide:  
a) Drawings in triplicate in sufficient detail to permit identification of the type of the rear fog 
lamp, state the detailed characteristic struct ures of the photometric mirror, and a copy of 
brief technical description wh ich concerns the optics unit da ta of the rear fog lamp, 
including the reference axis (H=0o, V=0o), reference centre a nd the geometric position for 
the installation of the rear fog lamp on the vehicle. 
b) Two sample lamps (the rear fog lamp equippe d with replaceable filament lamp shall be 
provided with filament lamp, the rear fog lamp with variable intensity shall be provided with 
a  dimmer). 
 6.2.3 each of the sample lamps shall be in conformity with the corresponding provisions specified in Article 4.1.  6.2.4 According to Clause 5 to carry out measuremen ts, both sample lamps shall be in conformity 
with the corresponding provisi ons specified in Article 4.2, Article 4.3 and Article 4.4. 
 6.3 The checking of the c onformity of production  
 6.3.1 With regard to the rear fog lamps that  have  been granted the Type Approval, use the sample 
lamps selected by random sampling from the mass-pr oduced lamps to determin e its conformity of 
production.  6.3.2 Both random sampled lamps shall be in conf ormity with the corresponding provisions in 
Article 4.1.  6.3.3 According to Clause 5 to ca rry out measurements, both the random sampled lamps shall be in 
conformity with the corresponding provisions in Ar ticle 4.2, Article 4.3 a nd Article 4.4, but among 
it the minimum luminous intensity shall be changed to 80% of th e specified value in Section 
4.2.1.2, the maximum luminous intensity shall be change d to 120% of the specified value in Section 
4.2.1.3.