SIST EN ISO 14182:2000
(Main)Animal feeding stuffs - Determination of residues of organophosphorus pesticides - Gas chromatographic method (ISO 14182:1999)
Animal feeding stuffs - Determination of residues of organophosphorus pesticides - Gas chromatographic method (ISO 14182:1999)
Futtermittel - Bestimmung von Organophosphorpestizid-Rückständen - Gaschromatographisches Verfahren (ISO 14182:1999)
Diese Internationale Norm legt ein gaschromatographisches Verfahren zur Bestimmung von Organophosphorpestizid-Rückständen in Futtermitteln fest. Das Verfahren ist auf Futtermittel anwendbar, die Rückstände von einem oder mehreren der folgenden Organophosphorpestizide enthalten: Azinphos-Ethyl, Azinphos-Methyl, Bromophos, Carbophenotion, Chlorpyrifos, Chlorpyrifos-Methyl, Diazinon, Dimethoat, Ethion, Fonofos, Malathion, Methidathion, Parathion, Parathion-Methyl, Primiphos-Ethyl und Primiphos-Methyl. Die untere Nachweisgrenze für diese Organophosphorpestizide ist 0,01 ug/g.
Aliments des animaux - Détermination des résidus de pesticides organo-phosphorés - Méthode par chromatographie en phase gazeuse (ISO 14182:1999)
La présente Norme internationale spécifie une méthode de détermination par chromatographie en phase gazeuse des résidus de pesticides organo-phosphorés dans les aliments des animaux.La méthode est applicable aux aliments des animaux contenant des résidus d'un ou plusieurs des pesticides organo-phosphorés suivants: azinphos-éthyl, azinphos-méthyl, bromophos, carbophénothion, chlorpyrifos, chlorpyrifos-méthyl, diazinon, diméthoate, éthion, fonofos, malathion, méthidathion, parathion, parathion-méthyl, pyrimiphos-éthyl et pyrimiphos-méthyl.La limite inférieure de détection de ces pesticides organo-phosphorés est de 0,01 µg/g.NOTE La méthode est probablement également applicable à d'autres pesticides organo-phosphorés tels que la méthaccrifos et le fénotrothion, mais elle n'a pas été validée pour ces pesticides.
Krma - Določevanje ostankov organofosfornih pesticidov - Plinska kromatografska metoda (ISO 14182:1999)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 14182:2000
01-maj-2000
.UPD'RORþHYDQMHRVWDQNRYRUJDQRIRVIRUQLKSHVWLFLGRY3OLQVNDNURPDWRJUDIVND
PHWRGD ,62
Animal feeding stuffs - Determination of residues of organophosphorus pesticides - Gas
chromatographic method (ISO 14182:1999)
Futtermittel - Bestimmung von Organophosphorpestizid-Rückständen -
Gaschromatographisches Verfahren (ISO 14182:1999)
Aliments des animaux - Détermination des résidus de pesticides organo-phosphorés -
Méthode par chromatographie en phase gazeuse (ISO 14182:1999)
Ta slovenski standard je istoveten z: EN ISO 14182:1999
ICS:
65.120 Krmila Animal feeding stuffs
SIST EN ISO 14182:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 14182:2000
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SIST EN ISO 14182:2000
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SIST EN ISO 14182:2000
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SIST EN ISO 14182:2000
INTERNATIONAL ISO
STANDARD 14182
First edition
1999-12-15
Animal feeding stuffs — Determination of
residues of organophosphorus
pesticides — Gas chromatographic method
Aliments des animaux — Détermination des résidus de pesticides organo-
phosphorés — Méthode par chromatographie en phase gazeuse
Reference number
ISO 14182:1999(E)
©
ISO 1999
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
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ii © ISO 1999 – All rights reserved
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
Contents Page
Foreword.iv
1 Scope .1
2 Normative references .1
3 Principle.1
4 Reagents and materials .1
5 Apparatus .3
6 Sampling.5
7 Preparation of test sample.5
8 Procedure .6
9 Expression of results .7
10 Confirmation of identity .8
11 Precision.8
12 Test report .8
Annex A (informative) Examples of gas chromatographic operating conditions for organophosphorus
pesticides .9
Annex B (informative) Results of interlaboratory tests.10
Bibliography.18
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SIST EN ISO 14182:2000
ISO 14182:1999(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 International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 14182 was prepared by Technical Committee ISO/TC 34, Agricultural food products,
Subcommittee SC 10, Animal feeding stuffs.
Annexes A and B of this International Standard are for information only.
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SIST EN ISO 14182:2000
INTERNATIONAL STANDARD ISO 14182:1999(E)
Animal feeding stuffs — Determination of residues of
organophosphorus pesticides — Gas chromatographic method
1 Scope
This International Standard specifies a gas chromatographic method for the determination of the residues of
organophosphorus pesticides in animal feeding stuffs.
The method is applicable to animal feeding stuffs containing residues of one or more of the following organo-
phosphorus pesticides: azinphos-ethyl, azinphos-methyl, bromophos, carbophenothion, chlorpyrifos, chlorpyrifos-
methyl, diazinon, dimethoate, ethion, fonofos, malathion, methidathion, parathion, parathion-methyl,
pirimiphos-ethyl and pirimiphos-methyl.
The lower limit of determination for these organophosphorus pesticides is 0,01�g/g.
NOTE The method is probably equally applicable to other organophosphorus pesticides such as methaccrifos and
fenitrothion, but it has not been validated for these pesticides.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard 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 documents referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 3696, Water for analytical laboratory use — Specification and test methods.
ISO 6498, Animal feeding stuffs — Preparation of test samples.
3Principle
A test portion is extracted with acetone. The filtered extract is diluted with water and a saturated sodium chloride
solution. The pesticides are partitioned in dichloromethane. The concentrated extract is purified on a
chromatographic column of 10 % water-deactivated silica gel. Gas chromatographic determination is carried out
with a phosphorus-selective detector or a mass-selective detector.
4 Reagents and materials
Use only reagents of recognized analytical grade and with a purity suitable for pesticide residue analysis.
Check the purity of the reagents by performing a blank test under the same conditions as used in the method. The
chromatogram should not show any interfering impurity.
WARNING — Some of the organic solvents are suspected carcinogens. Use with care.
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ISO 14182:1999(E)
4.1 Water, complying with at least grade 3 in accordance with ISO 3696.
4.2 Hexane
4.3 Acetone
4.4 Dichloromethane
4.5 Ethyl acetate
4.6 Silica gel, with a mass fraction of water of 10 %.
Activate silica gel 60, particle size 63 μm to 200 μm, at 130 °C overnight and cool in a desiccator. After cooling to
room temperature, pour the silica gel into an air-tight glass container and add sufficient distilled water to bring the
final mass fraction of water to 10 %. Shake the container mechanically or by hand vigorously for 30 s and allow to
stand for 30 min with occasional shaking. After 30 min the silica gel is ready for use. It may not be stored for more
than 6 h.
4.7 Eluting solvent, dichloromethane in hexane (50 % volume fraction).
Mix equal volumes of dichloromethane (4.4) and hexane(4.2).
4.8 Inert gas, e.g. nitrogen.
4.9 Sodium sulfate, anhydrous.
4.10 Sodium chloride saturated solution
4.11 Pesticide reference standards, as follows:
� azinphos-ethyl [S-(3,4-dihydro-4-oxobenzo[d][1,2,3]triazin-3-ylmethyl) O,O-diethyl phosphorodithioate];
� azinphos-methyl [S-(3,4-dihydro-4-oxobenzo[d][1,2,3]triazin-3-ylmethyl) O,O-dimethyl phosphorodithioate];
� bromophos [O-4-bromo-2,5-dichlorophenyl O,O-dimethyl phosphorothioate];
� carbophenothion [S-4-chlorophenylthiomethyl O,O-diethyl phosphorothioate];
� chlorpyrifos [O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate];
� chlorpyrifos-methyl [O,O-dimethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate];
� diazinon [O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate];
� dimethoate [O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate];
� ethion [O,O,O',O'-tetraethyl S,S'-methylene di(phosphorodithioate)];
� fonofos [O-ethyl S-phenyl ethylphosphonodithioate];
� malathion [diethyl (dimethoxythiophosphorylthio)succinate];
� methidathion [S-2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl O,O-dimethyl phosphorodithioate];
� parathion [O,O-diethyl O-4-nitrophenyl phosphorothioate];
� parathion-methyl [O,O-dimethyl O-4-nitrophenyl phosphorothioate];
� pirimiphos-ethyl [O-2-diethylamino-6-methylpyrimidin-4-yl O,O-diethyl phosphorothioate];
� pirimiphos-methyl [O-2-diethylamino-6-methylpyrimidin-4-yl O,O-dimethyl phosphorothioate];
NOTE The common names and the chemical names (between square brackets) according to IUPAC nomenclature, are in
accordance with ISO 1750 [1].
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ISO 14182:1999(E)
4.12 Internal standard: tributylphosphate.
4.13 Pesticide standard solutions
4.13.1 Stock solutions, of concentration 1 000 μg/ml.
Prepare a stock solution of each pesticide reference standard (4.11) and of the internal standard (4.12) as follows.
Weigh, to the nearest 0,1 mg, a mass of a pesticide reference standard (4.11) or the internal standard (4.12) which
will result in a solution with a content of reference standard or internal standard of 1 000 μg/ml. While weighing,
observe the cleanness of the standard material. Transfer the weighed mass into a volumetric flasks, dissolve in
ethyl acetate (4.5) and dilute to volume with ethyl acetate.
These solutions are stable for 6 months when stored at 4 °C in the dark.
4.13.2 Intermediate solutions, of concentration 10 μg/ml.
Pipette 1 ml of each stock solution (4.13.1) into individual 100 ml volumetric flasks. Dilute to volume with ethyl
acetate (4.5). The solutions are stable for 1 month when stored at 4 °C in the dark.
NOTE The stability of properly stored pesticide standards is very widely known. Investigations have shown that all neat
pesticide standards tested are stable for 15 years when stored at �18 °C and that stock solutions of pesticide standards in
toluene of 1 mg/kg are stable for at least 3 years when stored at �18 °C.
A recommended practice for longer storage is as follows. Transfer portions of the prepared standard solutions to
amber vials with PTFE-lined screwcaps. Weigh the vials and store at �20 °C. When needed, remove a vial from the
freezer, bring to room temperature and weigh. If accumulated loss in mass (due to evaporation) is 10 % or more of
the prefrozen net mass, discard the vial. Weigh and refreeze stock standards and intermediate solutions that are in
use for more than 1 month (usually in 25 ml vials). Otherwise, the prepared standard solutions (usually in 2 ml
vials) may be stored at 4 °C and shall be discarded after 1 month.
4.13.3 Working solutions, of concentration 0,5 μg/ml.
Pipette 5 ml of each intermediate solution (4.13.2) into 100 ml volumetric flasks and dilute to volume with ethyl
acetate (4.5). The solutions are stable for 1 month when stored at 4 °C in the dark (see 4.13.2).
4.14 Blank sample solutions, of the same type as the samples being analysed, but free of positives, resulting
from previous determinations.
5 Apparatus
Before use, wash all glassware thoroughly with detergent free of interfering substances, rinse with water, then with
acetone and dry.
Avoid the use of plastics containers and do not lubricate the stopcocks with grease, otherwise impurities could be
introduced into the solvents.
Usual laboratory equipment and in particular the following.
5.1 Separating funnels, of capacities 500 ml and 1000 ml, with polytetrafluoroethylene (PTFE) stopcocks and
stoppers.
5.2 Filtering flasks, of capacity 500 ml.
5.3 Büchner funnel, made of porcelain, with internal diameter 90 mm.
5.4 Graduated tubes, of capacity 10 ml, with polytetrafluoroethylene (PTFE) stoppers.
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
5.5 Glass chromatographic tube, about 300 mm in length, 8 mm to 10 mm internal diameter, with coarse fritted
plate of porosity grade P 100 (pore size index 40�mto100�m [2]) or glass wool plug.
5.6 Rotary vacuum evaporator, provided with round-bottom flasks of capacities 100 ml and 500 ml, and a water
bath set at 40 °C.
5.7 Mechanical shaker or high-speed blender
5.8 Gas chromatographic system
5.8.1 Components
The system shall comprise:
� splitless or on-column injection system;
� column;
� phosphorus-selective detector or mass-selective detector;
� electrometer;
� mV recorder or integrator;
� data-handling software and computer system.
Each injection port, column oven and detector shall be provided with an independent heating device controlled to
the nearest 0,1 °C.
The chromatographic system shall be adjusted and the parameters optimized according to the characteristics of the
instrument used.
5.8.2 Conditions
The injection port and the detector temperatures shall be 220 °C to 240 °C and 180 °C to 380 °C, respectively,
according to the manufacturer's instructions.
For organophosphorus separations with a capillary column, a temperature programme for the column oven is
recommended.
5.8.3 Injection device
An autosampler or any other adequate injection device may be used.
For manual injections, use a microsyringe of capacity 1 μl to 5 μl, with a needle length suitable for the mode of
injection (splitless or on-column).
Before injecting the solution into the gas chromatograph, rinse the syringe ten times with pure solvent, then
five times with solution. After injection, rinse the syringe five times with pure solvent.
5.8.4 Column
The use of capillary columns coated with nonpolar to mid-range polarity stationary phases, e.g. SE-30, SE-54,
OV-17, or equivalent, is recommended.
Standard glass columns, of length 2 m to 4 m and of internal diameter 2 mm to 4 mm, packed with 10 % DC-200 on
Chromosorb WHP 0,15 mm to 0,18 mm particle size, or a mixture of 2 % QF1 and 1,5 % DC-200 on
Chromosorb WHP 0,125 mm to 1,15 mm particle size, or any other stationary phases and inert supports
recommended for organophosphorus residue analyses could be used as an alternative.
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
The temperature programme for the column shall be chosen to separate the mixture of pesticides specified in
clause 1 into individual components (see annex A).
After installing a new column, it shall be conditioned for at least 48 h at a temperature slightly above the proposed
highest operating temperature, with carrier gas flowing through it.
5.8.5 Detector
Use a phosphorus-selective detector [flame photometric detector (FPD) or nitrogen-phosphorus detector (NPD) in
P mode] or mass-selective detector (MSD), with a minimum detection limit of 50 pg of P compounds.
5.8.6 Carrier gas
Use pure nitrogen, pure helium or pure hydrogen.
Dry the carrier gas by passing it through 0,5 nm molecular sieve traps, previously activated at 350 °C for 4 h to 8 h,
installed in the carrier gas line.
Reactivate the molecular sieves each time a new gas cylinder is assembled and as often as needed.
5.8.7 Auxiliary gases
Usehydrogenand air.
5.8.8 Verification of the linearity of the system
Check the linearity of the system from 0,1 ng to 2 ng of parathion.
Prepare working solutions with parathion contents ranging from 0,05 μg/ml to 1,0 μg/ml. Inject 2 μl.
Plot the peak size (area or height) against the mass, in nanograms, of parathion injected. The graph shall be a
straight line that passes through the origin. If not, establish the range of concentrations within which the detector
response is linear.
6 Sampling
Sampling is not part of the method specified in this International Standard. A recommended sampling method is
given in ISO 6497 [3].
It is important that the laboratory receive a sample which is truly representative and has not been damaged or
changed during transport or storage.
7 Preparation of test sample
Prepare the test sample in accordance with ISO 6498.
Grind a portion of the well-mixed laboratory sample (dry or low-moisture products, e.g. cereals and cereal products,
oilseeds and oilseed meals, mixed feeds, hay, etc.) so that it passes completely through a sieve with 1 mm
apertures. Mix thoroughly.
Chop high-moisture products (e.g. grasses, silages, etc.) into small pieces and mix thoroughly to obtain
homogeneous samples.
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8 Procedure
8.1 General
Carry out the following steps on both the prepared test sample (clause 7) and a blank sample (4.14) having a
matrix of the same type as the sample being analysed, for use in preparing the reference calibration solution.
8.2 Test portion
Weigh, to the nearest 0,1 g, 50 g of the prepared test sample (clause 7) for dry or low-moisture products, or 100 g
for high-moisture products, into a 1000 ml conical flask.
8.3 Extraction
Add enough water (4.1) to the test portion so that a total amount of water of about 100 g is obtained. Let the
sample soak for about 5 min. Add 200 ml of acetone (4.3). Close the flask tightly and shake for 2 h on a mechanical
shaker or homogenize for 2 min in a high-speed blender.
Filter the suspension with suction through a Büchner funnel (5.3), fitted with filter paper of medium porosity, into a
500 ml filtering flask (5.2). Wash the conical flask or the blender cup and the residue on the filter paper with two
25 ml portions of acetone, collecting the washings into the same filtering flask (5.2).
Transfer the filtrate to a 1 000 ml separating funnel. Wash the filtering flask (5.2) with 100 ml of dichloromethane
(4.4) and transfer this to the separating funnel. Add 250 ml of water (4.1) and about 50 ml of saturated sodium
chloride solution (4.10) into the separating funnel. Stopper and shake for 2 min.
Allow the phases to separate and draw off the lower phase (dichloromethane) into a 500 ml separating funnel.
Repeat twice with 50 ml of dichloromethane (4.4) and combine the extracts in the same 500 ml separating funnel.
Wash the dichloromethane extract with two 100 ml portions of water, discarding the washings.
Filter the dichloromethane extract through a filter paper containing about 20 g of sodium sulfate (4.9) into a 500 ml
flask of a vacuum evaporator. Rinse the separating funnel and the sodium sulfate with two 10 ml portions of
dichloromethane and add to the flask.
Concentrate to about 2 ml under vacuum at a temperature not exceeding 40 °C. Transfer the solution to a 10 ml
graduated tube using 1 ml to 2 ml of hexane (4.2) and concentrate under nitrogen to about 1 ml.
Do not allow the solution to dry out or losses of pesticides may occur because of volatility or poor solubility.
8.4 Column clean-up
8.4.1 Preparation of the column
Transfer 5 g of 10 % water-deactivated silica gel (4.6) into a glass chromatographic tube (5.5). Add 5 g anhydrous
sodium sulfate (4.9) on the top of the silica gel. Wash the prepared column with 20 ml of hexane (4.2).
NOTE Prepacked silica or Florisil cartridges (e.g. Millipore-SEP PAK) could be used instead of a silica gel column, after
checking for efficiency and absence of interferences.
8.4.2 Purification
Transfer quantitatively the concentrated extract (8.3) to the top of the prepared column (8.4.1) using 1 ml to 2 ml
portions of hexane (4.2).
Elute the organophosphorus pesticides with 50 ml of eluting solvent (4.7) and collect the eluate into a 100 ml flask
of a vacuum evaporator.
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
Concentrate the eluate as in 8.3 but using ethyl acetate (4.5) instead of hexane and dilute the final solution to 10 ml
with ethyl acetate for chromatography.
When an internal standard method is used, add 0,5 ml of the intermediate solution of tributylphosphate (4.13.2) to
the final extract before diluting to 10 ml with ethylacetate.
Keep the blank extract to prepare the reference calibration solution (8.5).
8.5 Gas chromatography
Equilibrate the gas chromatographic system under the recommended operating conditions (5.8). Inject 1 μl to 2 μl
of working standard solution (4.13.3), then the same volume of the sample extract (8.4.2). Dilute the sample extract
if necessary.
Identify the individual pesticide peaks on the basis of retention times.
Determine the amount of pesticides by comparing the size of the sample peaks with those of the known amount of
the corresponding pesticide peak in the working standard solution.
If the results correspond to or exceed the maximum residue limits (MRLs), prepare a reference calibration solution
by adding to the blank extract appropriate amounts of intermediate solutions (4.13.2) of those pesticides identified
in the sample solution, so that the size of the peaks of this reference solution is within 25 % of the size of the peaks
in the sample solution. Dilute to 10 ml with ethyl acetate (4.5). Inject into the gas chromatograph the same volume
as for the sample solution.
Determine the amount of pesticides by comparing the size of the sample peaks with those of the known amount of
the corresponding pesticide peak in the reference calibration solution.
9 Expression of results
9.1 Calculation
Calculate the content of each individual pesticide residue in the test sample by the equation:
Am��V
s
w �
Am��V
si
where
w is the individual pesticide residue content, in micrograms per gram, of the test sample;
A is the size of the sample peak;
A is the size of the corresponding standard pesticide peak in the working standard solution or the reference
s
calibration solution;
m is the mass, in nanograms, of standard pesticide injected into the gas chromatograph;
s
V is the final volume, in millilitres, of the sample extract taking into account any dilution that is necessary;
V is the volume, in microlitres, of the sample extract injected into the gas chromatograph;
i
m is the mass, in grams, of the test portion.
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SIST EN ISO 14182:2000
ISO 14182:1999(E)
9.2 Recovery
Verify the performance of the method by recovery experiments made on fortified blank samples at the 0,1 μg/g
level.
The recovery coefficient for each individual pesticide shall be between 70 % and 110 %.
NOTE When a residue exceeding a maximum residue limit (MRL) is to be confirmed, the concurrent recovery level should
be approximately similar to that of the sample.
10 Confirmation of identity
When the results correspond to or exceed the maximum residue limits (MRLs), a confirmation of identity is needed,
either by chromatography on a second column of significantly different polarity, or, where the apparatus is
available, by using GC-MS to quantify and confirm the identity of the pesticide.
11 Precision
11.1 Interlaboratory tests
Details of interlaboratory tests on the precision of the method, including a note on the validity of the precision
figures, are given in annex B. The values derived from these tests may not be applicable to concentration ranges
and matrices other than those given.
11.2 Repeatability
The absolute difference between two independent single test results, obtained using the same method on identical
test material in the same laboratory by the same operator using the same equipment within a short interval of time,
will in not more than 5 % of cases exceed the repeatability limit r derived from Tables B.1 to B.15.
11.3 Reproducibility
The absolute difference between two single test results, obtained using the same method on identical test material
in different laboratories by different operators using different equipment, will in not more than 5 % of cases exceed
the reproducibility limit R derived from Tables B.1 to B.15.
12 Test report
The test report shall specify:
� all information necessary for the complete identification of the sample;
� the sampling method used, if known;
� the test method used, with reference to this International Standard;
� all operating details not specified in this International Standard, or regarded as optional, together with details of
any incidents which may have influenced the test result(s);
� the test result obtained, or the two test results obtained if the repeatability has been checked.
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SIST EN ISO 14182:2000
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Annex A
(informative)
Examples of gas chromatographic operating conditions for
organophosphorus pesticides
Example 1
Column: fused silica capillary OV-1, length 25 m, internal diameter 0,25 mm, film thickness
0,25 μm
Column oven temperature: 60 °C for 2 min, then 20 °C/min to 130 °C, 6 °C/min to 240 °C, then 240 °C for 5 min
Injector: splitless with 45 s delay, 250 °C, or on-column, initial oven temperature
Detector: NPD in P mode, 280 °C, or MSD
Example 2
Column: fused silica capillary SE-54, length 25 m, internal diameter 0,25 mm, film thickness
0,25 μm
Column oven temperature: 60 °C for 0,5 min, then 30 °C/min to 130 °C, 8 °C/min to 240 °C, then 240 °C for 2 min
Injector: splitless with 45 s delay, 250 °C, or on-column, initial oven temperature
Detector: NPD in P mode, 280 °C, or MSD
Example 3
Column: fused silica capillary OV-17, length 30 m, internal diameter 0,25 mm, film thickness
0,25 μm
Column oven temperature: 60 °C for 0,5 min, then 30 °C/min to 160 °C, 6 °C/min to 280 °C, then 280 °C for 4 min
Injector: splitless, 250 °C, or on-column, initial oven temperature
Detector: NPD in P mode, 285 °C, or MSD
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ISO 14182:1999(E)
Annex B
(informative)
Results of interlaboratory tests
The precision of the method was established by an interlaboratory test organized by the Romanian standardization
1)
Association (ASRO) in 1996 and carried out in accordance with ISO 5725 [4]. In this test seven laboratories
participated. Samples of the following composition were investigated: 50
...
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