SIST EN 16237:2013

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.DKlassifizierung nicht elektrisch betriebener Quellen inkohärenter optischer StrahlungClassification des sources non électriques de rayonnement optique incohérentClassification of non-electrical sources of incoherent optical radiation17.240Merjenje sevanjaRadiation measurements17.180.20Barve in merjenje svetlobeColours and measurement of lightICS:Ta slovenski standard je istoveten z:EN 16237:2013SIST EN 16237:2013en,fr,de01-maj-2013SIST EN 16237:2013SLOVENSKI
STANDARD



SIST EN 16237:2013



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 16237
January 2013 ICS 17.180.20; 17.240 English Version
Classification of non-electrical sources of incoherent optical radiation
Classification des sources non électriques de rayonnement optique incohérent
Klassifizierung nicht elektrisch betriebener Quellen inkohärenter optischer Strahlung This European Standard was approved by CEN on 1 December 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
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EN 16237:2013 (E) 2 Contents Page Foreword . 3 Introduction . 4 1 Scope . 6 2 Normative references . 6 3 Terms and definitions . 6 4 Classification . 10 4.1 General . 10 4.2 Emission classes . 10 4.2.1 General . 10 4.2.2 UV-emissions potentially causing eye and skin hazards . 12 4.2.3 UV- and visible emissions potentially causing blue-light hazard . 12 4.2.4 Visible and IR-emissions potentially causing retinal thermal hazard . 13 4.2.5 Visible and IR-emissions potentially causing cornea and lens hazards and skin burning hazard . 13 4.3 Additional information for class 6 emissions . 14 4.4 Procedures for the classification for non-constant radiation emissions . 14 4.4.1 UV-emissions potentially causing eye and skin hazards . 14 4.4.2 UV- and visible emissions potentially causing blue-light hazard . 14 4.4.3 Visible and IR-emissions potentially causing retinal thermal hazard . 15 4.4.4 Visible and IR-emissions potentially causing cornea and lens hazards and skin burning hazard . 15 5 Procedures for determining optical radiation emissions . 15 5.1 General . 15 5.2 Physical quantities . 15 5.3 Measurement methods . 15 5.3.1 Selection of suitable methods . 15 5.3.2 Suitable apparatus . 15 5.3.3 Requirements . 15 5.4 Performing measurements . 17 5.4.1 General . 17 5.4.2 Operating conditions . 17 5.4.3 Measurement points . 18 5.4.4 Measurement time and duration . 19 5.4.5 Report of the measurements . 19 6 Marking . 20 7 Information for use . 21 Annex A (informative)
Rationale for the radiation emission classification . 22 A.1 Background for the emission class specifications . 22 A.2 Use of the source classification in a risk assessment . 23 Annex B (informative)
Classification reference values related to skin burn hazards . 25 Annex C (informative)
Suitable methods for measurement of optical radiation emissions . 27 Bibliography . 29
SIST EN 16237:2013



EN 16237:2013 (E) 3 Foreword This document (EN 16237:2013) has been prepared by Technical Committee CEN/TC 169 “Light and lighting”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2013, and conflicting national standards shall be withdrawn at the latest by July 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 16237:2013



EN 16237:2013 (E) 4 Introduction Optical radiation consists of the spectral regions covered by ultraviolet, visible and infrared radiation. Sources of incoherent optical radiation are used both in workplaces and privately. The radiation may intentionally be applied to carry out a specific task or may occur unintentionally as a by-product. Some sources are powered electrically, others are powered non-electrically, e.g. by gas or other fuels. Examples for non-electrically powered sources are burners, furnaces, heaters, gas welding, thermal cutting, chemical torches, hot materials etc.
People staying near to or working in the vicinity of such sources may be exposed to optical radiation. Depending on the level of exposure, injuries may occur to the skin and/or to the eyes. In order to avoid such injuries, European [1] and national legislation require the determination of exposures and the assessment of the associated risks in workplaces. In addition, maximum allowed optical radiation exposure limit values are set by legislation. Workers must not exceed these exposure limit values. If necessary, exposure reduction measures have to be applied. Optical radiation exposures can be determined by several procedures: measurements, calculations, derivations from source emission data, etc. Not all of these procedures are appropriate in every case. Exposure measurements can be made in accordance with EN 14255-1 and EN 14255-2, but are expensive and time consuming. Generally, it is preferable to carry out a risk assessment without expensive measurements, if possible. Calculations of exposures may be done with the aid of software such as Catrayon1) [3], but not in all cases. If quantitative emission data from the source are available, the user may in some cases estimate the possible exposure of people in the vicinity of the radiation source.
A simpler approach for risk assessment is the classification of the optical radiation emissions. If such an emission classification is available, the user may easily assess the risk from use of the source. Emission classifications are already provided by standards for laser devices (EN 60825-1) [8] and for machinery (EN 12198-1) [7] as well as for lamps and lamp systems (EN 62471) [9]. This present standard provides a specific emission classification for non-electrically powered optical radiation sources. The classification in this standard is intended to be user-friendly. The emission classes depend on the duration ûtmax beyond which the exposure limit values of the European directive on artificial optical radiation 2006/25/EC [1] may be exceeded. By comparing the actual exposure duration occurring at the workplace with ûtmax, the user can easily estimate if the exposure limit values may or may not be exceeded. Therefore, for a classified source, a risk assessment as required by Directive 2006/25/EC can easily be carried out. The measurement of the optical radiation emission for the classification of the source is always carried out at a standard distance and at greater distances if that is where emission is at the maximum. Therefore, this classification represents the worst case exposure. This is appropriate if people are likely to be in the vicinity. However, sources are often operated in such a way that people will be further away than the worst-case location. For these applications, a classification shall be made not only for the worst case, but in addition for normal use conditions. The source classification measurements shall then be made for several distances around the source including the normal operating distance(s). As a result, emission classes are produced depending on the distance or even iso-emission-class lines around the source. The user is then able to estimate more easily the maximum possible exposure under normal use conditions and also under worst case conditions.
1) Catrayon is an example of a suitable software available commercially. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN or CENELEC of this product. SIST EN 16237:2013



EN 16237:2013 (E) 5 There is a limitation of the concept of risk assessment with classified sources. A risk assessment can only be carried out if the classified source contributes predominantly to the optical radiation exposure of people. If there are several optical radiation sources that significantly contribute to the exposure, the risk assessment has to be carried out in a different way, e.g. by measurement of the exposure and comparison with the exposure limit values. In many cases however, one source will be predominant and an easy risk assessment can be carried out using the emission classification. Therefore, emission classification of a source forms a practical approach. SIST EN 16237:2013



EN 16237:2013 (E) 6 1 Scope This European Standard provides a scheme for the classification of artificial non-electrical sources of incoherent optical radiation with regard to their radiation emissions. It helps users of the sources to easily carry out a risk assessment when people can be exposed to radiation from the sources.
This standard applies for sources emitting optical radiation in the wavelength between 180 nm and 3 000 nm.
This standard does not apply for electrically powered sources. This standard does not apply for machinery, for laser devices and for lamps and lamp systems. NOTE A classification for machinery is given in EN 12198-1 [7], a classification for laser devices is given in EN 60825-1 [8] and a classification for lamps and lamp systems is given in EN 62471 [9]. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 14255-1:2005, Measurement and assessment of personal exposures to incoherent optical radiation — Part 1: Ultraviolet radiation emitted by artificial sources in the workplace EN 14255-2:2005, Measurement and assessment of personal exposures to incoherent optical radiation — Part 2: Visible and infrared radiation emitted by artificial sources in the workplace EN 14255-4:2006, Measurement and assessment of personal exposures to incoherent optical radiation — Part 4: Terminology and quantities used in UV-, visible and IR-exposure measurements ISO 7010, Graphical symbols — Safety colours and safety signs — Registered safety signs ENV 13005, Guide to the expression of uncertainty in measurement
3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 14255-4:2006 and the following apply. 3.1 emission class characteristic of an optical source which reflects the level of optical radiation emission at a specified distance Note 1 to entry: Emission classes in this standard are correlated to maximum exposure durations ûtmax according to Tables 2, 3, 4 and 5. 3.2 maximum exposure duration
ûtmax time duration up to which a person being exposed to optical radiation does not exceed the exposure limit values Note 1 to entry: Exposure limit values associated with ûtmax in this standard are taken from the European Directive on artificial optical radiation 2006/25/EC [1]. SIST EN 16237:2013



EN 16237:2013 (E) 7 3.3 irradiance
E quotient of the radiant power incident on an element of a surface by the area of that element
Note 1 to entry: See also CIE 17.4 [5]. Note 2 to entry: The irradiance E may be defined for a specified wavelength-band, e.g. 315 nm to 400 nm (UV-A), 380 nm to 3 000 nm (visible and IR-A and IR-B), 780 nm to 3 000 nm (IR-A and IR-B). 3.4 ultraviolet hazard irradiance
Es irradiance spectrally weighted with the ultraviolet hazard weighting function s, given by: λλλΕλλλd)()(21ssE∫= (1) [SOURCE: EN 14255-4] Note 1 to entry: Values for the function s(λ) are specified in EU directive 2006/25/EC in the wavelength range 180 nm to 400 nm. 3.5 retinal thermal radiance
Lr radiance spectrally weighted with the retinal thermal hazard weighting function r(λ)I given by:
∫=21d)( )(λλλλλλrLLr (2) [SOURCE: EN 14255-4] Note 1 to entry: The retinal thermal radiance can be defined in specific wavelength bands e.g. 380 nm to 1 400 nm and 780 nm to 1 400 nm. See Table 4. 3.6 blue-light radiance
Lb radiance spectrally weighted with the blue-light hazard weighting function b(λ), given by:
∫=21d)()(λλλλλλbLLb (3) [SOURCE: EN 14255-4] Note 1 to entry: Values for the function b(λ) are specified in EU directive 2006/25/EC in the wavelength range 300 nm to 700 nm. 3.7 blue-light irradiance
Eb irradiance spectrally weighted with the blue-light hazard weighting function b, given by: SIST EN 16237:2013



EN 16237:2013 (E) 8 ∫=21d)()(λλλλλλbEEb (4) [SOURCE: EN 14255-4] Note 1 to entry: Values for the function b(λ) are specified in EU directive 2006/25/EC in the wavelength range 300 nm to 700 nm
3.8 optical radiation electromagnetic radiation in the wavelength range between 100 nm and 1 mm 3.9 incoherent optical radiation optical radiation with no constant phase-relationship between any two points in space and time Note 1 to entry: In practice, this means optical radiation other than laser radiation. 3.10
angular subtense of the source . plane angle in radians under which a source is seen from the point of observation, given by: α = D / r
(5 a) where D diameter of the source
r distance between source and point of observation If the surface of the source is not perpendicular to the line of sight, the diameter of the source D is replaced by the viewing source diameter DL. In this case, the angular subtense of the source . is given by: α = DL / r
(5 b) where DL viewing source diameter (see EN 14255-4) r distance between source and point of observation SIST EN 16237:2013



EN 16237:2013 (E) 9
a)
b) Key 1
source
r distance between source and point of observation 2
detector
angle of acceptance
3
aperture
φ viewing angle . angular subtense of the source
DL viewing source diameter (see EN 14255-4) D diameter of the source Figure 1 — Angle of acceptance
of the detector and angular subtense . of the source (simplified drawings) SIST EN 16237:2013



EN 16237:2013 (E) 10 3.11 source diameter
D diameter of the circle, if the source is circular, or arithmetic mean of the longest and shortest geometric dimension, if the source is oblong [SOURCE: EN 14255-4] 3.12
angle of acceptance
largest plane angle between all directions in which a radiation detector is sensitive
Note 1 to entry: In practical applications the angle of acceptance is determined by both the choice of an aperture and the distance between this aperture and the detector (see Figure 1a).
Note 2 to entry: The angle of acceptance
is a property of a radiation detector. It should not be confused with the angular subtense .I which is a property of the radiation source. [SOURCE: EN 14255-4] 4 Classification 4.1 General The radiation emissions of the source shall be determined by measurement or reliable estimation. Measurements shall be done according to Clause 5. Subsequently the source shall be assigned a class between 0 and 6, based upon the measured or reliably estimated emissions, according to the classification scheme in 4.2.
The classification shall be done for each wavelength band (ultraviolet, visible and infrared) and for all quantities specified in Tables 1 to 5. In wavelength bands where the emissions are reliably known to be insignificant, the source can be assigned to Class 0. The highest emission class of all quantities in all wavelength bands shall then be assigned to the source. Emission measurements for the classification of the source shall be carried out at points specified in 5.4.3. Hence the emission class finally assigned to the source represents the worst case when people may be exposed to the source.
If the assigned emission class is greater than 0, it shall be provided in the information for use of the source and marked on the source. If during normal use of the source people stay farther than the distance for which the standard worst-case classification is done (see 5.4.3.1), then classifications shall also be done for the distance(s) of the normal use (see 5.4.3.2). The emissions in different normal use conditions shall then be determined and iso-emission-class lines around the source shall be provided (see 5.4.3.2).
NOTE Under some unusual conditions of use (such as servicing, maintenance or repair) the classification might no longer be valid.
4.2 Emission classes 4.2.1 General Emission classes are specified in Tables 2 to 5 depending on the optical radiation emission levels with respect to the following quantities:  ultraviolet hazard irradiance Es (180 nm to 400 nm); SIST EN 16237:2013



EN 16237:2013 (E) 11  irradiance E (315 nm to 400 nm);  blue-light radiance Lb (300 nm to 700 nm);  blue-light irradiance Eb (300 nm to 700 nm);  retinal thermal radiance Lr (380 nm to 1 400 nm);
 retinal thermal radiance Lr (780 nm to 1 400 nm);  irradiance E (780 nm to 3 000 nm);  irradiance E (380 nm to 3 000 nm). NOTE 1 The emission classes in Tables 2 to 5 are specified for emission levels which correlate to exposure durations ûtmax beyond which the exposure limit values of the European Directive on artificial optical radiation 2006/25/EC [1] may be exceeded.
NOTE 2
Measurement quantities are designated with different names in standards and in the EU-Directive 2006/25/EC. In Table 1, the quantity names used in EN 14255-1, EN 14255-2, EN 14255-4 and in this standard are listed together with the equivalent names used in EU-Directive 2006/25/EC. The wavelength ranges in which the quantities are applied are the same in the standards and the EU-Directive.
Table 1 — Names of measuring quantities in EN 14255-1, EN 14255-2, EN 14255-4 and this standard and equivalent names for the same quantities in EU-Directive 2006/25/EC Name of quantity in EN 14255-1, EN 14255-2, EN 14255-4 and this standard Name of quantity in EU-Directive 2006/25/EC Es (180 nm to 400 nm) ultraviolet hazard irradiance Eeff
effective irradiance E (315 nm to 400 nm) irradiance
EUVA total irradiance (UVA) Lb (300 nm to 700 nm) blue light radiance
LB effective radiance (blue light)
Eb (300 nm to 700 nm) blue light irradiance EB effective irradiance (blue light) Lr (380 nm to 1 400 nm) retinal thermal radiance
LR effective radiance (thermal injury) (used in wavelength 380 nm to 1 400 nm) Lr (780 nm to 1 400 nm)
retinal thermal radiance LR effective radiance (thermal injury) (used in wavelength 780 nm to 1 400 nm) E (780 nm to 3 000 nm) irradiance EIR total irradiance (thermal injury) E (380 nm to 3 000 nm) irradiance Eskin total irradiance (visible, IRA and IRB) SIST EN 16237:2013



EN 16237:2013 (E) 12 4.2.2 UV-emissions potentially causing eye and skin hazards Emission classes with respect to UV-emissions potentially causing eye and skin hazards are specified in Table 2.
Table 2 — Source classification by radiation emissions with respect to ultraviolet hazard irradiance Es (180 nm to 400 nm) and UV-A irradiance E (315 nm to 400 nm) Emission class ûtmax Es (180 nm to 400 nm) mW/m² E (315 nm to 400 nm) W/m² 0 24 h ≤ 0,m5 ≤ 0,N2 1 8 h 0,35 < Es ≤ N,0
0,12 < E ≤ 0,m5 2 2,5 h 1,0 < Es ≤ m,m 0,35 < E ≤ N,N 3 1 h 3,3 < Es ≤ 8,m 1,1 < E ≤ 2,8 4 20 min 8,3 < Es ≤ 25 2,8 < E ≤ 8,m 5 5 min 25 < Es ≤ N00 8,3 < E ≤ mm 6 < 5 min
> 100 > 33
NOTE The term ultraviolet hazard irradiance Es as defined in EN 14255-4 is equivalent to the term effective irradiance Eeff in the EU Directive 2006/25/EC [1]; irradiance E (315 nm to 400 nm) as defined in EN 14255-4 is equivalent to the term EUVA in the EU Directive 2006/25/EC [1]. 4.2.3 UV- and visible emissions potentially causing blue-light hazard
Emission classes with respect to UV- and visible emissions potentially causing blue-light hazard are specified in Table 3.
Table 3 — Source classification by radiation emissions with respect to blue-light radiance Lb (300 nm to 700 nm) and blue-light irradiance Eb (300 nm to 700 nm) Emission class ûtmax Lb W/(m²sr) Eb
mW/m² 0 24 h ≤ N00 ≤ N0 1 8 h -
-
2 2,5 h
100 < Lb ≤ NNN
10 < Eb ≤ NN 3 1 h 111 < Lb ≤ 278 11 < Eb ≤ 28 4 20 min 278 < Lb ≤ 8mm 28 < Eb ≤ 8m 5 5 min 833 < Lb ≤ mmmm 83 < Eb ≤ mmm 6 < 5 min
> 3 333 > 333 NOTE 1 Blue-light radiance Lb is equivalent to effective radiance (blue light) LB in the EU Directive 2006/25/EC [1]; blue-light irradiance Eb is equivalent to effective irradiance (blue light) EB in the EU Directive 2006/25/EC [1]. NOTE 2 For classification regarding blue-light radiance and irradiance there is no emission class 1. NOTE 3 The classification in column Eb is only relevant to intended fixated viewing of small sources with an angular subtense α less than 11 mrad.
SIST EN 16237:2013



EN 16237:2013 (E) 13 4.2.4 Visible and IR-emissions potentially causing retinal thermal hazard Emission classes with respect to visible and IR-emissions potentially causing retinal thermal hazard are specified in Table 4.
Table 4 — Source classification by radiation emissions with respect to retinal thermal radiance Lr (380 nm to 1 400 nm) and Lr (780 nm to 1 400 nm) Emission class ûtmax Lr (380 nm to 1400 nm) W/(m²sr) Lr (780 nm to 1400 nm) W/(m²sr) 0 24 h ≤ 2,8 * 107/Cα
≤ 6 * 106/Cα
1 8 h -
-
2 2,5 h -
-
3 1 h -
-
4 20 min -
-
5 5 min -
-
6 < 5 min > 2,8 * 107/Cα > 6 * 106/Cα NOTE For classification regarding retinal thermal radiance there are no emission classes 1 to 5.
In order to classify a source with respect to the retinal thermal radiance Lr (380 nm to 1 400 nm) not only Lr (380 nm to 1 400 nm) shall be measured but also the angular subtense α of the source. For sources with an angular subtense α less than or equal to 1,7 mrad, Cα shall be set to 1,7. For sources with an angular substance α between 1,7 mrad and 100 mrad, Cα is equal to α, but is dimensionless.
For sources with an angular subtense α equal to or larger than 100 mrad, Cα shall be set to 100.
In order to classify a source with respect to the retinal thermal radiance Lr (780 nm to 1 400 nm) not only Lr (780 nm to 1 400 nm) shall be measured but also the angular subtense α of the source. For sources with an angular subtense α less than or equal to 11 mrad, Cα shall be set to 11. For sources with an angular substance α between 11 mrad and 100 mrad, Cα is equal to α, but is dimensionless.
For sources with an angular subtense α equal to or larger than 100 mrad, Cα shall be set to 100. 4.2.5 Visible and IR-emissions potentially causing cornea and lens hazards and skin burning hazard Emission classes with respect to visible and IR-emissions potentially causing cornea and lens hazards and skin burning hazard are specified in Table 5.
SIST EN 16237:2013



EN 16237:2013 (E) 14 Table 5 — Source classification by radiation emissions with respect to irradiance E (780 nm to 3 000 nm) potentially causing cornea and lens hazards and irradiance E (380 nm to 3 000 nm) potentially causing skin burning hazard Emission class ûtmax E
(780 nm to 3 000 nm) W/m2 E (380 nm to 3 000 nm) W/m2 0 24 h ≤ 100 < 300 1 8 h - - 2 2,5 h -
300 < E ≤ 580 3 1 h -
580 < E ≤ 660 4 20 min
-
660 < E ≤ 690 5 5 min 100 < E ≤ 250
690 < E ≤ NN00 6 < 5 min
> 250 > 1100 NOTE 1 Irradiance E (780 nm to 3 000 nm) is equivalent to EIR in the EU Directive 2006/25/EC [1]; irradiance E (380 nm to 3 000 nm) is equivalent to Eskin in the EU Directive 2006/25/EC [1]. NOTE 2 For classification regarding cornea and lens hazards, there are no emission classes 1 to 4 specified by the emission value E (780 nm to 3 000 nm).
NOTE 3 For classification regarding the skin burning hazard, there is no emission class 1 specified by the emission value E (380 nm to 3 000 nm). NOTE 4 Values of E (380 nm to 3 000 nm) for the specification of emission classes are derived from a calculation model for pain sensation and standard specification for heat stress; see Annex B.
4.3 Additional information for class 6 emissions If, for any quantity specified in 4.2, the determined emission value exceeds the upper reference value of class 5 then the value(s) shall be indicated.
NOTE This additional information supports carrying out risk assessments according to EU Directive 2006/25/EC.
4.4 Procedures for the classification for non-constant radiation emissions 4.4.1 UV-emissions potentially causing eye and skin hazards For time varying UV emissions, the classification reference values specified in Table 2 apply as mean values averaged over the corresponding ûtmax. The measurement period shall be carefully selected such that ûtmax includes the maximum emission of which the source is capable. 4.4.2 UV- and visible emissions potentially causing blue-light hazard
For time varying UV- and visible emissions, the classification reference values specified in Table 3 apply as mean values averaged over the corresponding ûtmax. The measurement period shall be carefully selected such that ûtmax includes the maximum emission of which the source is cap
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