SIST EN ISO 11254-1:2000
(Main)Lasers and laser-related equipment - Determination of laser-induced damage threshold of optical surfaces - Part 1: 1 on 1 test (ISO 11254-1:2000)
Lasers and laser-related equipment - Determination of laser-induced damage threshold of optical surfaces - Part 1: 1 on 1 test (ISO 11254-1:2000)
This Standard specifies a test method for determining the single shot laser radiation induced damage threshold of optical surfaces.
Laser und Laseranlagen - Bestimmung der laserinduzierten Zerstörschwelle optischer Oberflächen - Teil 1: 1 auf 1 Prüfung (ISO 11254-1:2000)
Dieser Teil von ISO 11254 legt ein Prüfverfahren fest zur Bestimmung der laserstrahlungsinduzierten Einzelschuß-Zerstörschwelle optischer Oberflächen. Dieses Prüfverfahren ist anwendbar für alle Kombinationen von Laserwellenlängen und Pulsdauern. Trotzdem kann der Vergleich von Zerstörschwellen-Daten irreführend sein, wenn die Messungen nicht bei identischen Wellenlängen, Pulsdauern und Strahldurchmessern durchgeführt wurden. Dieser Teil von ISO 11254 ist vorläufig beschränkt auf die irreversible Beschädigung von optischen Oberflächen.
Lasers et équipements associés aux lasers - Détermination du seuil d'endommagement provoqué par laser sur les surfaces optiques - Partie 1: Essai 1 sur 1 (ISO 11254-1:2000)
La présente partie de l'ISO 11254 spécifie une méthode d'essai de détermination du seuil d'endommagement causé sur les surfaces optiques par un rayonnement laser simple. Cette procédure d'essai s'applique à toutes les différentes combinaisons de longueur d'onde et de durée d'impulsion de laser. Toutefois, la comparaison des données du seuil d'endommagement peut être erronée, à moins que les mesures aient été effectuées avec une même longueur d'onde, une même durée d'impulsion et un même diamètre de faisceau. La présente partie de l'ISO 11254 est provisoirement limitée aux dommages irréversibles des surfaces optiques.
NOTE : Des exemples pour les unités et échelles de seuil d'endommagement causé par laser sont donnés en annexe C. AVERTISSEMNT - L'extrapolation des données d'endommagement peut conduire à des résultats de calcul erronés et à une surestimation du seuil d'endommagement. Dans le cas des matériaux toxiques (par exemple: ZnSe, GaAs, CdTe, ThF4, chalcogénides, Be, Cr, Ni), cela peut conduire à de sérieux risques pour la santé. Voir en annexe C pour des commentaires supplémentaires.
Laserji in laserska oprema - Ugotavljanje praga poškodbe na optični površini, povzročene z laserjem - 1. del: Preskus 1 na 1 (ISO 11254-1:2000)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 11254-1:2000
01-november-2000
/DVHUMLLQODVHUVNDRSUHPD8JRWDYOMDQMHSUDJDSRãNRGEHQDRSWLþQLSRYUãLQL
SRY]URþHQH]ODVHUMHPGHO 3UHVNXVQD ,62
Lasers and laser-related equipment - Determination of laser-induced damage threshold
of optical surfaces - Part 1: 1 on 1 test (ISO 11254-1:2000)
Laser und Laseranlagen - Bestimmung der laserinduzierten Zerstörschwelle optischer
Oberflächen - Teil 1: 1 auf 1 Prüfung (ISO 11254-1:2000)
Lasers et équipements associés aux lasers - Détermination du seuil d'endommagement
provoqué par laser sur les surfaces optiques - Partie 1: Essai 1 sur 1 (ISO 11254-
1:2000)
Ta slovenski standard je istoveten z: EN ISO 11254-1:2000
ICS:
31.260 Optoelektronika, laserska Optoelectronics. Laser
oprema equipment
SIST EN ISO 11254-1:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 11254-1:2000
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SIST EN ISO 11254-1:2000
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SIST EN ISO 11254-1:2000
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SIST EN ISO 11254-1:2000
INTERNATIONAL ISO
STANDARD 11254-1
First edition
2000-06-01
Laser and laser-related equipment —
Determination of laser-induced damage
threshold of optical surfaces —
Part 1:
1-on-1 test
Lasers et équipements associés aux lasers — Détermination du seuil
d’endommagement provoqué par laser sur les surfaces optiques —
Partie 1: Essai 1 sur 1
Reference number
ISO 11254-1:2000(E)
©
ISO 2000
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
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ii © ISO 2000 – All rights reserved
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
Contents
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Symbols and units.3
5 Sampling.4
6 Test method.4
6.1 Principle.4
6.2 Apparatus .5
6.3 Preparation of test specimens .8
6.4 Procedure .9
7 Evaluation.9
8 Accuracy.10
9 Test report .10
Annex A (informative) Test report example.12
Annex B (informative) Example of a measurement procedure.15
Annex C (informative) Units and scaling of laser-induced damage thresholds .21
Bibliography.22
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO 11254 may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 11254-1 was prepared by Technical Committee ISO/TC 172, Optics and optical
instruments, Subcommittee SC 9, Electro-optical systems.
ISO 11254 consists of the following parts, under the general title Laser and laser-related equipment —
Determination of laser-induced damage threshold of optical surfaces:
� Part 1: 1-on-1 test
� Part 2: S-on-1 test
Annexes A, B and C of this part of ISO 11254 are for information only.
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
Introduction
Optical components can be damaged by laser irradiation of sufficiently high energy or power. At any specified laser
irradiation level, the probability for laser damage is usually higher for the surface of a component than for the bulk.
Thus the limiting value of an optical component is usually given by the damage threshold of its surface.
This part of ISO 11254 describes a standard procedure for determining the laser-induced damage threshold (LIDT)
of optical surfaces, both coated and uncoated. The procedure has been promulgated in order to provide a method
for obtaining consistent measurement results, which may be rapidly and accurately compared among different
testing laboratories. In order to simplify the comparison of laser-damage measurement facilities, laser groups are
defined in this part of ISO 11254.
This part of ISO 11254 is applicable to single-shot testing only (1-on-1 tests). For multi-shot testing (S-on-1) refer to
ISO 11254-2.
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SIST EN ISO 11254-1:2000
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SIST EN ISO 11254-1:2000
INTERNATIONAL STANDARD ISO 11254-1:2000(E)
Laser and laser-related equipment — Determination
of laser-induced damage threshold of optical surfaces —
Part 1:
1-on-1 test
1 Scope
This part of ISO 11254 specifies a test method for determining the single-shot laser radiation-induced damage
threshold (LIDT) of optical surfaces.
This test procedure is applicable to all combinations of different laser wavelengths and pulse lengths. However
comparison of laser damage threshold data may be misleading unless the measurements have been carried out at
identical wavelengths, pulse lengths and beam diameters.
Application of this part of ISO 11254 is provisionally restricted to irreversible damage of optical surfaces.
NOTE Examples of units and scaling of laser-induced damage thresholds are given in annex C.
WARNING — The extrapolation of damage data can lead to inaccurate or wrong calculated results and to
an overestimation of the LIDT. In the case of toxic materials (e.g. ZnSe, GaAs, CdTe, ThF , chalcogenides,
4
Be, Cr, Ni) this could lead to severe health hazards.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 11254. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 11254 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 10110-7:1996, Optics and optical instruments — Preparation of drawings for optical elements and systems —
Part 7: Surface imperfection tolerances.
ISO 11145:1994, Optics and optical instruments — Lasers and laser-related equipment — Vocabulary and
symbols.
3 Terms and definitions
For the purposes of this part of ISO 11254, the terms and definitions given in ISO 11145 and the following apply.
3.1
surface damage
any permanent laser radiation-induced change of the surface characteristics of the specimen which can be
observed by an inspection technique described within this part of ISO 11254
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
3.2
1-on-1 test
test programme that uses one shot of laser radiation on each unexposed site on the specimen surface
3.3
threshold
highest quantity of laser radiation incident upon the optical surface for which the extrapolated probability of damage
is zero
NOTE The quantity of laser radiation may be expressed as energy density H or power density E (see annex C).
max max
3.4
target plane
plane tangential to the surface of the specimen at the point of intersection of the test laser beam axis with the
surface of the specimen
3.5
effective area
A
T,eff
ratio of power [pulse energy] to maximum power [energy] density
NOTE 1 For spatial beam profiling perpendicular to the direction of beam propagation and angles of incidence differing from
0 rad, the cosine of the angle of incidence is included in the calculation of the effective area. In this case, the effective area may
be approximated by the following formulae:
Q
A � (1)
T,eff
H cos(� )
max
P
A � (2)
T,eff
E cos()�
max
NOTE 2 For the special case of a circular flat-top beam profile with diameter d , the effective area is given by:
100
2
Q Hd� 1
max 100 2
A �� � �d (3)
T,eff 100
H 4H 4
max max
For a focused Gaussian beam (circular beam) with a beam diameter d86,5, the effectiveareaisgiven by:
22
xy�
� 8
��
2
d
2
86,5
8r
Hxeddy
max �
�� �
2
d
Q 1
���� 86,5 2
Ae�� �2d�rr��d (4)
T,eff 86,5
�
HH 8
max max
0
With the definition of the second moment of the energy density distribution function H(x,y,z) at the location z,
� 2�
2
rH(,r��)r ddr
z z
2 0 0
� ()z � (5)
� 2�
Hr(,��)rddr
z z
0 0
and the definition of the beam diameter d as a function of the second moment
�
dz()�22�()z (6)
�
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
theeffective area canbeexpressedinthefollowingforms:
1 1
22 2
a) flat-top beam: Ad����d� 2��;(d�d 7)
T,eff 100��100
4 4
1 1
22 2
b) Gaussian beam: Ad����d��� ;d�d (8)
T,eff 86,5��
86,5
8 8
3.6
effective beam diameter
d
T,eff
double the square root of the effective area divided by the factor pi
A
T,eff
d � 2 (9)
T,eff
�
3.7
effective pulse duration
ratio of total pulse energy to maximum pulse power
4 Symbols and units
Table 1 — Symbols and units of measurement
Symbol Unit Term
nm wavelength
�
� rad angle of incidence
p
degree of polarization
d mm beam diameter in the target plane
T
d mm effective beam diameter in target plane
T,eff
2
A cm effective area in the target plane
T,eff
t
ns, μs, s pulse duration
H
t
ns, μs, s effective pulse duration (see 6.2.6.2)
eff
Q
J pulse energy
P
W peak pulse power
pk
P
W power
2
H J/cm maximum energy density
max
2
E
W/cm maximum power density
max
2
H
J/cm threshold energy density
th
2
E W/cm threshold power density
th
F W/cm threshold linear power density
th
N total number of sites for the test
TS
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
5 Sampling
Either a functional component or a witness specimen shall be tested. If a witness specimen is tested, the substrate
material and surface finish shall be the same as for the component, and the witness specimen shall be coated in
the same coating run as the component. The coating run number and date shall be identified for the test
component.
6 Test method
6.1 Principle
The basic approach to laser damage testing is shown in Figure 1. The output of a well-characterized stable laser is
set to the desired energy or power with a variable attenuator, and delivered to the specimen located at or near the
focus of a focussing system. The use of a focussing system permits the generation of destructive energy densities
or power densities at the test specimen.
Key
1 Sample compartment 5 Waveplate
2 On-line damage detector 6 Variable attenuator
3 Beam diagnostic 7 Laser system
4 Focussing system
Figure 1 — Basic approach to 1-on-1 laser damage testing
The specimen is mounted in a manipulator which is used to position different test sites in the beam and set the
angle of incidence. The polarization state is set with an appropriate waveplate. The incident laser beam is sampled
with a beamsplitter which directs a portion of the beam to a diagnostic unit. The beam diagnostic unit permits
simultaneous determination of the total pulse energy and the spatial and temporal profiles.
Microscopic examination of the testing site before and after irradiation is used to detect damage.
The specimen is positioned at different non-overlapping test sites in reference to the beam, and irradiated at
different energy densities or power densities. From these data the damage threshold can be determined.
This procedure is applicable to testing with all laser systems, irrespective of pulse length and wavelength. Pulse
durations widely used in industrial and scientific applications are summarized and grouped in Table 2.
4 © ISO 2000 – All rights reserved
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
Table 2 — Laser groups
Group Description Pulse duration
1 very short pulse 1 ns to 3 ns
2 short pulse 10 ns to 30 ns
3 medium pulse 1 �sto3 �s
4 long pulse 200 �sto1000 �s
5 pulse length to be specified
6cw 1s
NOTE Damage thresholds of pulsed lasers (Groups 1 to 4) are usually expressed in units of energy density
2
(J/cm ). The pulse duration of the test laser shall be documented in the test report. Group 6: Damage thresholds of
continuous-wave (cw) lasers are usually expressed in units of linear power density (W/cm). Power density refers to
the average power during the irradiation time. Examples for units of laser-induced damage thresholds are described
in annex C.
6.2 Apparatus
6.2.1 Laser, delivering pulses with a reproducible near-Gaussian or near-flat-top spatial profile.
The temporal profile of the pulses is monitored during the measurement. For the different laser groups, the
maximum allowable variations of the pulse parameters are compiled in Table 3. As a minimum specification of a
laser system of Group 5, the pulse-to-pulse variation of the maximum power density shall be less than � 20 %.
Stability criteria for the beam parameters shall be determined and documented in an error budget.
Table 3 — Maximum percentage variation of laser parameters and corresponding percentage variation
of maximum pulse power density E
max
Laser
Pulse energy Average power Pulse duration Effective area Power density
group
QP � A E
av eff T,eff max
1 �5— � 10 � 10 � 15
2 �5— � 5 � 6 � 10
3 �5— � 5 � 6 � 10
4 �5— � 5 � 6 � 10
6— �5— � 6 � 20
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
6.2.2 Variable attenuator and beam delivery system
The laser output shall be attenuated to the required level with an external variable attenuator that is free of drifts in
transmissivity and imaging properties.
The beam delivery system and the attenuator shall not affect the properties of the laser beam in a manner
inconsistent with the tolerances given in 6.2.1. In particular, the polarization state of the laser beam shall not be
altered by the beam delivery system.
6.2.3 Focussing system
The arrangement of the focussing system should be adapted to the special requirements of the laser system and to
the intended beam profile in the target plane. The specific arrangement and the parameters of the focussing
system shall be documented in the test report. The specifications of the active area and the energy density shall be
referred to the location of the test surface.
For Gaussian beams, it is advisable to select an aperture of the focussing system which amounts to not less than
three times the beam diameter at the entrance of the focussing system. A minimum effective f-number of 50 and a
beam diameter in the target plane of not less than 0,8 mm are recommended. The target plane should be located
at or near the focal waist formed by the focussing system. For Groups 3 to 6, the beam diameter may be reduced
depending on the power density necessary, but should not be smaller than 0,2 mm. In such cases the effective
f-number may be reduced below a value of 50.
For near-flat-top laser beams, it is advisable to position the test surface in the image plane of the focussing system
with a focal length > 0,2 m that forms an image of a suitable aperture in the optical path.
Coherence effects in specimens with parallel surfaces can occur and affect the measurement. These effects shall
be eliminated by appropriate techniques, such as wedging or tilting of the specimen. The application of a highly
converging beam is also a practical method for removing coherence effects in the specimen.
6.2.4 Specimen holder
The test station shall be equipped with a manipulator which allows for a precise placement of the test sites on the
specimen with an accuracy sufficient for the specimen size.
6.2.5 Damage-detection microscope, to inspect the surface before and after the test.
The investigations shall be made with an incident light microscope having Nomarski-type differential interference
contrast. A magnification in the range from 100� to 150� shall be used.
NOTE 1 For routine inspection and objective measurement of laser damage, an image analyser may be attached to the
microscope.
NOTE 2 An appropriate on-line damage detection system may be installed for evaluating the state of the surface under test or
for switching off the laser in long-pulse and cw damage-measurement facilities to avoid catastrophic damage of the specimen.
For on-line detection, any appropriate technique may be used. Techniques suited to this purpose are for instance on-line
microscopic techniques in conjunction with image analysers, photoacoustic and photothermal detection, as well as scatter
measurements using a separate laser or radiation from the damaging laser. A typical set-up for an on-line scatter measurement
system is described in ISO 11254-2.
6.2.6 Beam diagnostics
6.2.6.1 Measurement of total pulse energy and power
The diagnostic package shall be equipped with a calibrated detector to measure the pulse energy or beam power
delivered to the target plane. This instrument shall be traceable to a national standard with an absolute uncertainty
of � 5 % or better.
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
6.2.6.2 Temporal profile analysis
The diagnostic package shall include suitable instrumentation for analysing the temporal profile of the laser to
determine the pulse duration. The temporal profile shall be integrated to determine the ratio of total pulse energy Q
to maximum pulse power P . This ratio is called the effective pulse duration t :
pk eff
�
Pt() dt
z
Q
0
t�� (10)
eff
P P
pk pk
For pulsed lasers (Groups 1 to 4), upper limits for the temporal resolution of the pulse duration measurement are
defined in Table 4. For Group 6 lasers, the temporal stability of the output shall be determined with a resolution of
less than 10 ms. For lasers not included in Table 4, the upper limit of the temporal resolution shall not exceed 10 %
of the effective pulse duration.
Table 4 — Upper limits for the temporal resolution of the pulse duration measurement
Group Temporal resolution
1 100 ps
21ns
3 100 ns
410μs
6.2.6.3 Spatial profile
In all cases, the spatial profile shall be analysed in the target plane or an equivalent plane. The diagnostic package
shall be equipped with instrumentation to measure the two-dimensional spatial profile with a spatial resolution of
1,5 % of the beam diameter or better.
The maximum energy density or power density of the beam shall be determined as follows:
The two-dimensional profile shall be integrated to determine the ratio of total pulse energy Q to maximum energy
density H or the ratio of power P to maximum power density E , respectively. The effective area A is
max max T,eff
deduced from the formulae:
� �
Hx(,y)ddx y
z z
Q
����
A �� (11)
T,eff
H H
max max
� �
Exy(, )ddx y
z z
P
����
A �� (12)
T,eff
E E
max max
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
The maximum energy density H is given by
max
Q
H � (13)
max
A
T,eff
The maximum power density E is given by
max
H
max
E � (14)
max
t
eff
The maximum power density E is given by
max
P
E � (15)
max
A
T,eff
The testing equipment shall be characterized by the following parameters:
a) wavelength,�;
b) angle of incidence,�;
c) degree of polarization, p;
d) beam diameter in the target plane, d ;
T
e) effective beam diameter in the target plane, d ;
T,eff
f) pulse duration, t ;
H
g) effective pulse duration, t ;
eff
h) (minimum) number of sites tested at each energy density value;
i) total number of sites per test, N .
TS
6.3 Preparation of test specimens
Wavelength, angle of incidence and polarization of the laser radiation as used in the test shall be in accordance
with the specifications by the manufacturer for normal use. If ranges are given for the values of these parameters,
an arbitrary combination of wavelength, angle of incidence and polarization within these ranges may be used.
Carry out storage, cleaning and preparation of the specimens in accordance with the specimen specifications
provided by the manufacturer for normal use.
In the absence of manufacturer-specified instructions, use the following procedure.
a) Store the specimen at less than 50 % relative humidity for 24 h prior to testing. Handle the specimen by the
non-optical surfaces only.
b) Before testing, carry out a microscopic evaluation of surface quality and cleanliness in accordance with
ISO 10110-7 using a Nomarski/darkfield microscope at 150� magnification or higher.
c) If contaminants are seen on the specimen, the surface shall be cleaned. The cleaning procedure shall be
documented. If the contaminants are not removable, document them by photographic and/or electronic means
before testing.
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
d) Inspect the test site for dust particles during irradiation. The test environment shall be clean, filtered air of less
than 50 % relative humidity and shall be documented.
e) The test sites shall be in a defined and reproducible arrangement. Refer the test grid to fixed reference points
on the specimen. It is acceptable to make marks at known locations on the specimen as reference points only
after testing is completed and before the specimen is removed from the specimen positioner.
NOTE It is usually possible to use one or more large damage spots as reference points, rather than potentially
contaminating the surface of the specimen. This is preferable if there is any likelihood of having to make further tests on the
specimen.
6.4 Procedure
A number of test sites are positioned into the beam and irradiated at different energy densities or power densities.
From this data, the damage threshold can be determined. Test a minimum of 10 sites for each energy-density or
power-density increment. The range of pulse energies or beam powers employed shall be sufficiently broad to
include points of zero damage frequency, as well as points of 100 % damage probability.
7 Evaluation
Damage threshold data are obtained by the damage-probability method. Expose a minimum of ten sites to one
pulse energy (or beam power) and record the fraction of sites which are damaged. Repeat this procedure for other
pulse energies or beam powers to develop a plot of damage probability versus energy or power. An example is
shown in Figure 2. Linear extrapolation of the damage probability data to zero damage probability yields the
threshold energy. Convert the threshold value to the appropriate threshold energy density H or threshold power
th
density E as described in 6.2.6.3.
th
Figure 2 — Diagram for the determination of the damage threshold from experimental data
(damage to KBr windows, 50 pieces,� 40 mm, BMFT 315-5691 ATT 2249 A/8)
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SIST EN ISO 11254-1:2000
ISO 11254-1:2000(E)
In the case of a laser system with a high pulse-to-pulse energy variation, it is permissible to expose the specimen
to arbitrary pulse energies and to sort the data with respect to appropriate energy intervals after the experiment. A
minimum of ten sites shall be tested within one energy interval.
NOTE For an efficient measurement procedure with maximum accuracy for a given number of sites, an appropriate
example is described in annex B.
8 Accuracy
Prepare a calibration error budget to determine the overall measurement accuracy. Variations in the total energy or
beam power, spatial profile, and temporal profile shall be included in the error budget.
An example for Group 3 lasers is given in Table 5. Similar formats are appropriate for other laser groups.
Table 5 — Error budget for a Group 3 laser-damage testing facility
Random variations:
Pulse-to-pulse energy stability � 3%
Pulse-to-pulse spatial profile stability � 5%
Pulse-to-pulse temporal profile stability � 5%
Systematic variations:
Calorimeter calibration � 3%
Calorimeter-energy monitor correlation � 2%
Overall energy density measurement reproducibility � 5,8 %
Overall energy density measurement uncertainty � 6,8 %
Overall power density measurement reproducibility � 7,7 %
Overall power density measurement uncertainty � 8,5 %
9 Test report
To guarantee a reliable in-process documentation, each specimen tested is assigned a unique run number, which
accompanies it through the test process from initial receipt to submission of the final report. All pertinent information
pertaining to test station configurations, source calibration, cleaning, microscopic inspections, exposure
parameters, raw data and reduced test results shall be traceable to this run number. This data shall be retained by
the test laboratory as a primary permanent reference.
F
...
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