ASTM D5836-20

Standard Test Method for Determination of 2,4-Toluene Diisocyanate (2,4-TDI) and 2,6-Toluene Diisocyanate (2,6-TDI) in Workplace Atmospheres (1-2 PP Method)

SIGNIFICANCE AND USE
5.1 Diisocyanates are used in the production of polyurethane foams, plastics, elastomers, surface coatings, and adhesives (5, 6). It has been estimated that the production of TDI will steadily increase during the future years.  
5.2 Diisocyanates are irritants to eyes, skin, and mucous membrane and are respiratory sensitizers. Chronic exposure to low concentrations of diisocyanates produces an allergic sensitization which may progress into asthmatic bronchitis (7, 8).  
5.3 The United States Occupational Safety and Health Administration (OSHA) has a permissible exposure limit (PEL) for 2,4-TDI of 0.02 ppm or 0.14 mg/m3 as a ceiling limit. There is no OSHA PEL for 2,6-TDI (9). The American Conference of Governmental Industrial Hygienists (ACGIH) has a time–weighted average (TWA) Threshold Limit Value (TLV) of 0.001 ppm or 0.007 mg/m3 and a short-term exposure limit (STEL) of 0.005 ppm or 0.036 mg/m3 for either 2,4-TDI, or 2,6-TDI, or for a mixture of 2,4- and 2,6-TDI (10).
SCOPE
1.1 This test method describes the determination of 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI) in air samples collected from workplace atmospheres in a cassette containing a glass-fiber filter impregnated with 1-(2-pyridyl)piperazine (1-2 PP). This procedure is effective for determining the vapor content of atmospheres. It is advisable to perform a field extraction for atmospheres containing aerosols to avoid the possibility of an underestimation.  
1.2 This test method uses a high-performance liquid chromatograph (HPLC) equipped with a fluorescence or an ultraviolet (UV) detector (1-4).2,3 An ultra high performance liquid chromatograph (UPLC) can also be used, provided that its performance is equivalent to what is stated in this standard.  
1.3 The validated range of the test method, as written, is from 1.4 to 5.6 μg of 2,4-TDI and 2,6-TDI which is equivalent to approximately 9.8 to 39 ppb for 2,4-TDI and 2,6-TDI based on a 20-L air sample. The HPLC method using an UV detector is capable of detecting 0.078 μg of 2,4-TDI and 0.068 μg of 2,6-TDI in a 4.0-mL solvent volume, which is equivalent to 0.55 ppb for 2,4-TDI and 0.48 ppb for 2,6-TDI based on a 20-L air sample.  
1.4 The isomers of 2,4-TDI and 2,6-TDI can be separated utilizing a reversed phase column for the HPLC method. Because industrial applications employ an isomeric mixture of 2,4- and 2,6-TDI, the ability to achieve this separation is important.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See Section 9 for specific precautions.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 29-Feb-2020
• ICS: 13.040.30 - Workplace atmospheres
• Technical Committee: D22 - Air Quality
• Drafting Committee: D22.04 - Workplace Air Quality

Relations

• Replaces: ASTM D5836-08(2013) - Standard Test Method for Determination of 2,4-Toluene Diisocyanate (2,4-TDI) and 2,6-Toluene Diisocyanate (2,6-TDI) in Workplace Atmospheres (1-2 PP Method)
• Effective Date: 01-Mar-2020
• Refers: ASTM D1356-20a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Sep-2020
• Refers: ASTM D1356-20 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Mar-2020
• Refers: ASTM D3686-20 - Standard Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activated Charcoal Tube Adsorption Method)
• Effective Date: 01-Mar-2020
• Refers: ASTM D1357-95(2019) - Standard Practice for Planning the Sampling of the Ambient Atmosphere
• Effective Date: 01-Aug-2019
• Refers: ASTM D4840-99(2018)e1 - Standard Guide for Sample Chain-of-Custody Procedures
• Effective Date: 15-Aug-2018
• Refers: ASTM D1356-15a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Oct-2015
• Refers: ASTM D1356-15 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Jul-2015
• Refers: ASTM D1356-14b - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-Dec-2014
• Refers: ASTM D1356-14a - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 01-May-2014
• Refers: ASTM D1356-14 - Standard Terminology Relating to Sampling and Analysis of Atmospheres
• Effective Date: 15-Jan-2014
• Refers: ASTM E691-13 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-May-2013
• Refers: ASTM D3686-13 - Standard Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activated Charcoal Tube Adsorption Method)
• Effective Date: 01-Apr-2013
• Refers: ASTM D5337-11 - Standard Practice for Flow Rate for Calibration of Personal Sampling Pumps
• Effective Date: 15-Nov-2011
• Refers: ASTM E691-11 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Nov-2011

Overview

ASTM D5836-20 establishes the standard test method for the determination of 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI) concentrations in workplace atmospheres using the 1-(2-pyridyl)piperazine (1-2 PP) method. Diisocyanates, including TDI, are widely used in the manufacture of polyurethane foams, coatings, adhesives, elastomers, and plastics. Monitoring airborne TDI levels is critical due to the compounds' recognized respiratory risks, skin and mucous membrane irritation, and potential to cause occupational asthma. This test method provides a validated procedure for sampling and analyzing workplace air to ensure regulatory compliance and worker safety.

Key Topics

• Workplace Exposure Monitoring: Addresses the need for reliable measurement of 2,4-TDI and 2,6-TDI to assess and control occupational exposure.
• Sampling Method: Utilizes air samples collected on glass-fiber filters impregnated with 1-2 PP, which reacts with TDIs to form a stable compound for analysis.
• Analytical Procedure: Involves extraction followed by analysis with high-performance liquid chromatography (HPLC) using either a fluorescence or ultraviolet (UV) detector. Ultra high performance liquid chromatography (UPLC) may also be used if equivalent.
• Sensitivity and Range: The method accurately detects TDI concentrations as low as approximately 0.55 ppb for 2,4-TDI and 0.48 ppb for 2,6-TDI in a 20-L air sample.
• Quality Control: Includes calibration and standardization procedures to ensure accuracy and traceability, as well as recommendations for handling interferences and maintaining sample integrity.
• Health and Safety: Outlines safety precautions for handling TDI chemicals and reagents, emphasizing protective equipment and proper laboratory practices.

Applications

• Industrial Hygiene Programs: Essential for companies producing or using polyurethane-derived products, helping monitor and minimize worker exposure to TDI.
• Regulatory Compliance: Supports adherence to Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs) and American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs) for 2,4-TDI and 2,6-TDI.
• Workplace Risk Assessment: Facilitates the identification of TDI exposure risks in sectors such as plastics, manufacturing, construction, and automotive industries.
• Incident Investigation: Utilized in occupational health investigations and air quality studies following potential TDI exposure events.
• Environmental Monitoring: Can be adapted for stationary air sampling in facilities to evaluate ambient concentrations and effectiveness of engineering controls.

Related Standards

For an integrated approach to workplace air quality monitoring and method validation, refer to the following related standards:

• ASTM D1193: Specification for reagent water used in analytical procedures.
• ASTM D1356: Terminology relating to sampling and analysis of atmospheres.
• ASTM D1357: Guidance on planning the sampling of the ambient atmosphere.
• ASTM D3686: Practice for sampling atmospheres to collect organic compound vapors.
• ASTM D5337: Practice for adjusting the flow rate of personal sampling pumps.
• ASTM D4840: Guide for sample chain-of-custody procedures.
• ASTM E691: Practice for conducting interlaboratory studies to determine the precision of a test method.
• ISO/IEC 17025: General requirements for the competence of testing and calibration laboratories.

---

By following ASTM D5836-20 for the determination of 2,4-TDI and 2,6-TDI, organizations can ensure a scientifically rigorous and internationally recognized approach to workplace air monitoring, worker protection, and regulatory compliance in industries that utilize diisocyanates. Proper implementation aids in exposure risk reduction, supports occupational health and safety programs, and demonstrates due diligence in maintaining safe working environments.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5836 − 20
Standard Test Method for
Determination of 2,4-Toluene Diisocyanate (2,4-TDI) and 2,6-
Toluene Diisocyanate (2,6-TDI) in Workplace Atmospheres
(1-2 PP Method)
This standard is issued under the fixed designation D5836; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.1 This test method describes the determination of 2,4-
responsibility of the user of this standard to establish appro-
toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate
priate safety, health, and environmental practices and deter-
(2,6-TDI) in air samples collected from workplace atmo-
mine the applicability of regulatory limitations prior to use.
spheres in a cassette containing a glass-fiber filter impregnated
See Section 9 for specific precautions.
with 1-(2-pyridyl)piperazine (1-2 PP). This procedure is effec-
1.7 This international standard was developed in accor-
tive for determining the vapor content of atmospheres. It is
dance with internationally recognized principles on standard-
advisable to perform a field extraction for atmospheres con-
ization established in the Decision on Principles for the
taining aerosols to avoid the possibility of an underestimation.
Development of International Standards, Guides and Recom-
1.2 This test method uses a high-performance liquid chro-
mendations issued by the World Trade Organization Technical
matograph (HPLC) equipped with a fluorescence or an ultra-
Barriers to Trade (TBT) Committee.
2,3
violet (UV) detector (1-4). An ultra high performance liquid
chromatograph (UPLC) can also be used, provided that its 2. Referenced Documents
performance is equivalent to what is stated in this standard.
2.1 ASTM Standards:
1.3 The validated range of the test method, as written, is D1193 Specification for Reagent Water
from 1.4 to 5.6 µg of 2,4-TDI and 2,6-TDI which is equivalent
D1356 Terminology Relating to Sampling and Analysis of
to approximately 9.8 to 39 ppb for 2,4-TDI and 2,6-TDI based Atmospheres
on a 20-Lair sample. The HPLC method using an UV detector
D1357 Practice for Planning the Sampling of the Ambient
is capable of detecting 0.078 µg of 2,4-TDI and 0.068 µg of
Atmosphere
2,6-TDI in a 4.0-mL solvent volume, which is equivalent to
D3686 Practice for Sampling Atmospheres to Collect Or-
0.55ppbfor2,4-TDIand0.48ppbfor2,6-TDIbasedona20-L
ganic Compound Vapors (Activated Charcoal Tube Ad-
air sample.
sorption Method)
D4840 Guide for Sample Chain-of-Custody Procedures
1.4 The isomers of 2,4-TDI and 2,6-TDI can be separated
D5337 Practice for Flow RateAdjustment of Personal Sam-
utilizing a reversed phase column for the HPLC method.
pling Pumps
Because industrial applications employ an isomeric mixture of
E691 Practice for Conducting an Interlaboratory Study to
2,4- and 2,6-TDI, the ability to achieve this separation is
Determine the Precision of a Test Method
important.
2.2 Other Documents:
1.5 The values stated in SI units are to be regarded as
ISO/IEC 17025 General requirements for the competence of
standard. No other units of measurement are included in this
testing and calibration laboratories
standard.
3. Terminology
This test method is under the jurisdiction of ASTM Committee D22 on Air
3.1 Definitions:
Quality and is the direct responsibility of Subcommittee D22.04 on Workplace Air
Quality.
Current edition approved March 1, 2020. Published May 2020. Originally
approved in 1995. Last previous edition approved in 2013 as D5836 – 08 (2013). For referenced ASTM standards, visit the ASTM website, www.astm.org, or
DOI: 10.1520/D5836-20. contactASTM Customer Service at [e-mail]. ForAnnual Book ofASTM
Validationdataandapreliminary draftof thistest methodwereprovidedbythe Standards volume information, refer to the standard’s Document Summary page on
Salt Lake Technical Center of the U.S. Dept. of Labor, Occupational Safety and the ASTM website.
Health Administration, Salt Lake City, UT. Available from International Organization for Standardization (ISO), ISO
The boldface numbers in parentheses refer to a list of references at the end of Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
this standard. Geneva, Switzerland, http://www.iso.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5836 − 20
3.1.1 For definitions of terms used in this test method, refer 7. Apparatus
to Terminology D1356.
7.1 Sampling Equipment:
4. Summary of Test Method
7.1.1 Personal Sampling Pumps, any pump capable of
sampling at a rate of about 1.0 L/min for 8 h.
4.1 A known volume of air is drawn through a cassette
containing a glass-fiber filter impregnated with 1-(2- 7.1.2 Flowmeter,portable,withanaccuracythatissufficient
pyridyl)piperazine. The diisocyanate reacts with the secondary
to enable the volumetric flow rate to be measured to within
amine to form a urea derivative.
65 %. The flowmeter calibration by a provider accredited to
ISO/IEC 17025 for such calibrations shall be traceable to
4.2 Thecoatedglass-fiberfilterisextractedwithacetonitrile
national or international standards. Retain the calibration
(ACN) containing 10 % dimethyl sulfoxide (DMSO) and the
certificate, including the pressure and temperature at which the
extract is analyzed by HPLC. The eluent is monitored with a
calibration was performed, and identifying and performance
fluorescence detector (240-nm excitation, 370-nm emission
cutoff filter) or a UV detector (254 nm). The identity of a documentation for the flowmeter.
chromatographic peak with a second UV wavelength is rec-
7.1.3 Glass-Fiber Filters, 37 mm, free of organic binder,
ommended if no fluorescence detector is utilized.
impregnated with 1.0 mg of 1-(2-pyridyl)piperazine.
4.3 The amount of the urea derivative collected is deter-
7.1.4 Cassette, plastic holders of the three-piece personal
mined by comparison of sample response (peak area integra-
monitor type, that accept filters of 37-mm diameter. Number
tions or peak heights) to a standard calibration curve for the
the cassette for identification.
urea derivative.
7.1.5 Cellulose Backup Pad, sized to fit the cassette (7.1.4).
4.4 The amount of diisocyanate is calculated from the
7.1.6 (Optional) Glass Vial, fitted with polytetrafluoroeth-
amount of urea determined in the analysis.
ylene (PTFE)-lined caps, containing 4.0-mL of extraction
solution (8.6). Number the vial for identification.
5. Significance and Use
7.2 Analytical Equipment:
5.1 Diisocyanates are used in the production of polyure-
thane foams, plastics, elastomers, surface coatings, and adhe-
7.2.1 Liquid Chromatograph, a high-performance liquid
sives (5, 6). It has been estimated that the production of TDI
chromatograph (HPLC) equipped with a fluorescence detector
will steadily increase during the future years.
capable of monitoring 240-nm excitation and 370-nm cutoff or
a UV detector capable of monitoring 254-nm wavelength and
5.2 Diisocyanates are irritants to eyes, skin, and mucous
a manual or automatic sample injector. A second UV wave-
membrane and are respiratory sensitizers. Chronic exposure to
length is recommended for identify confirmation if no fluores-
low concentrations of diisocyanates produces an allergic sen-
sitization which may progress into asthmatic bronchitis (7, 8). cence detector is utilized. An ultra high performance liquid
chromatography(UPLC)providingatleastthesameorequiva-
5.3 The United States Occupational Safety and Health
lent performance of HPLC can be also used.
Administration (OSHA) has a permissible exposure limit
7.2.2 Liquid Chromatographic Column, an HPLC stainless
(PEL) for 2,4-TDI of 0.02 ppm or 0.14 mg/m as a ceiling
limit. There is no OSHA PEL for 2,6-TDI (9). The American steel column capable of separating the urea derivatives. Ana-
Conference of Governmental Industrial Hygienists (ACGIH) lytical column recommended in this test method are the
has a time–weighted average (TWA) Threshold Limit Value following: a 25-cm by 4.6-mm inside diameter stainless steel
(TLV)of0.001ppmor0.007mg/m andashort-termexposure
column packed with 10-µm C8 or an equivalent column.
limit (STEL) of 0.005 ppm or 0.036 mg/m for either 2,4-TDI,
7.2.3 Electronic Integrator, an electronic integrator or some
or 2,6-TDI, or for a mixture of 2,4- and 2,6-TDI (10).
other suitable method of determining peak areas or heights.
7.2.4 Pipets and Volumetrics, various sizes of volumetric
6. Interferences
pipets and flasks to prepare standards.
6.1 Any compound having the same retention time as the
7.2.5 Syringe Operated Filter Unit, syringes with 4 mm,
standards is a possible interference. Generally, chromato-
polyvinylidene fluoride 0.2-µm pore size filter unit, or any
graphic conditions can be altered to resolve an interference.
equivalent device.
6.2 Compounds that can react with an isocyanate represent
7.2.6 HPLC Autosampler Vials, amber glass vials with
a potential interference. These would include molecules con-
PTFE-coated septums.
taining the functional groups: amines, alcohols, anhydrides,
7.2.7 Reciprocating Shaker, a reciprocating shaker or any
phenols, and carboxylic acids.
other equivalent device.
6.3 Strong oxidizing agents can potentially react with the
1-(2-pyridyl)piperazine.
8. Reagents and Materials
6.4 Retention time data on a single column is not definitive
8.1 Purity of Reagents—Reagent grade chemicals shall be
proof of chemical identity. Analysis by an alternate column
used in all tests. It is intended that all reagents shall conform to
system, ratioing of wavelength response using two wave-
the specifications of the Committees onAnalytical Reagents of
lengths or types of detector, should be performed to confirm
chemical identity. the American Chemical Society, where such specifications are
D5836 − 20
available. Other grades may be used provided it can be 10.2 Adjust the personal sampling pumps to the recom-
demonstrated that they are of sufficiently high purity to permit mended flow rate with an assembled cassette between the
their use without decreasing the accuracy of the determination. pump and the flow-measuring device in accordance to Practice
D5337. After the sampling, perform a post sampling flow rate
8.2 Purity of Water—Unless otherwise indicated, reference
verification. If the post sampling flow rate varies more than
water shall be understood to mean Type II reagent water
65 % from the recommended flow rate, invalidate the sample.
conforming to Specification D1193, HPLC grade.
10.3 Equip the worker, whose exposure is to be evaluated,
8.3 Acetonitrile (CH CN)—HPLC grade.
with a filter holder connected to a belt-supported sampling
8.4 Ammonium Acetate (CH COONH )—HPLC grade.
3 4
pump. Collect personal samples by pointing the sampler
8.5 Dimethyl Sulfoxide ((CH ) SO)—HPLC grade. downward in the breathing zone of the worker and remove the
3 2
top for open-face sampling. Draw air through the filter at a
8.6 Extracting Solution—A solvent mixture of acetonitrile
calibrated rate of approximately 1.0 L/min and collect a
and dimethyl sulfoxide in the percentage of 90 and 10 (v/v),
maximum air sample of 15 L. Use a tripod or other support to
respectively.
locate the sampler in the general room area for stationary
8.7 Glacial Acetic Acid (CH COOH)—Reagent grade.
monitoring.
8.8 Hexane (C H )—HPLC grade.
6 14 10.4 (Optional) Field Extraction (this procedure should be
done only if airbone aerosols of TDI are expected)—
8.9 Methylene Chloride (CH Cl )—HPLC grade.
2 2
Immediately after sampling, open the cassette, withdraw the
8.10 Mobile Phase—A solvent mixture of acetonitrile (8.3)
glass-fiber filter using forceps and insert, with the exposed
andwaterinthepercentageof37.5and62.5(v/v),respectively.
surface of the filter in direct contact with the liquid, into the
Addtothemobilephaseenoughammoniumacetate(8.4)(1.54
associated glass vial containing the extracting solution. Close
to 7.7 g/L of solution or 0.02 to 0.1 N) to optimize the
the glass vial.
chromatographic resolution. Add acetic acid (8.7)tothe
10.5 Treatfieldblanksinthesamemannerassamples.Open
mixture to lower the pH to 6.0 to 6.2.
them in the environment to be sampled and immediately close
8.11 1-(2-Pyridyl)piperazine (1-2 PP) (C H N )—Reagent
9 13 3
and
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5836 − 08 (Reapproved 2013) D5836 − 20
Standard Test Method for
Determination of 2,4-Toluene Diisocyanate (2,4-TDI) and 2,6-
Toluene Diisocyanate (2,6-TDI) in Workplace Atmospheres
(1-2 PP Method)
This standard is issued under the fixed designation D5836; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method describes the determination of 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI)
in air samples collected from workplace atmospheres in a cassette containing a glass-fiber filter impregnated with 1-(2-
pyridyl)piperazine (1-2 PP). This procedure is very effective for determining the vapor content of atmospheres. Atmospheres
containing aerosols may cause TDI results to be underestimated.It is advisable to perform a field extraction for atmospheres
containing aerosols to avoid the possibility of an underestimation.
1.2 This test method uses a high-performance liquid chromatograph (HPLC) equipped with a fluorescence or an ultraviolet (UV)
2,3
detector (1-4). An ultra high performance liquid chromatograph (UPLC) can also be used, provided that its performance is
equivalent to what is stated in this standard.
1.3 The validated range of the test method, as written, is from 1.4 to 5.6 μg of 2,4-TDI and 2,6-TDI which is equivalent to
approximately 9.8 to 39 ppb for 2,4-TDI and 2,6-TDI based on a 20-L air sample. The HPLC method using an UV detector is
capable of detecting 0.078 μg of 2,4-TDI and 0.068 μg of 2,6-TDI in a 4.0-mL solvent volume, which is equivalent to 0.55 ppb
for 2,4-TDI and 0.48 ppb for 2,6-TDI based on a 20-L air sample.
1.4 The isomers of 2,4-TDI,2,4-TDI and 2,6-TDI,2,6-TDI can be separated utilizing a reversed phase column for the HPLC
method. Because industrial applications employ an isomeric mixture of 2,4- and 2,6-TDI, the ability to achieve this separation is
important.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use. See Section 9 for specific precautions.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1193 Specification for Reagent Water
D1356 Terminology Relating to Sampling and Analysis of Atmospheres
D1357 Practice for Planning the Sampling of the Ambient Atmosphere
D3686 Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activated Charcoal Tube Adsorption Method)
D4840 Guide for Sample Chain-of-Custody Procedures
D5337 Practice for Flow Rate Adjustment of Personal Sampling Pumps
This test method is under the jurisdiction of ASTM Committee D22 on Air Quality and is the direct responsibility of Subcommittee D22.04 on Workplace Air Quality.
Current edition approved April 1, 2013March 1, 2020. Published April 2013May 2020. Originally approved in 1995. Last previous edition approved in 20082013 as
D5836 – 08.D5836 – 08 (2013). DOI: 10.1520/D5836-08R13.10.1520/D5836-20.
Validation data and a preliminary draft of this test method were provided by the Salt Lake Technical Center of the U.S. Dept. of Labor, Occupational Safety and Health
Administration, Salt Lake City, UT.
The boldface numbers in parentheses refer to the a list of references at the end of this test method.standard.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5836 − 20
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 Other Documents:
ISO/IEC 17025 General requirements for the competence of testing and calibration laboratories
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology D1356.Definitions:
3.1.1 For definitions of terms used in this test method, refer to Terminology D1356.
4. Summary of Test Method
4.1 A known volume of air is drawn through a cassette containing a glass-fiber filter impregnated with 1-(2-pyridyl)piperazine.
The diisocyanate reacts with the secondary amine to form a urea derivative.
4.2 The coated glass-fiber filter is extracted with acetonitrile (ACN) containing 10 % dimethyl sulfoxide (DMSO) and the
extract is analyzed by HPLC. The eluent is monitored with a fluorescence detector (240-nm excitation, 370-nm emission cutoff
filter) or a UV detector (254 nm). The identity of a chromatographic peak with a second UV wavelength is recommended if no
fluorescence detector is utilized.
4.3 The amount of the urea derivative collected is determined by comparison of sample response (peak area integrations or peak
heights) to a standard calibration curve for the urea derivative.
4.4 The amount of diisocyanate is calculated from the amount of urea determined in the analysis.
5. Significance and Use
5.1 Diisocyanates are used in the production of polyurethane foams, plastics, elastomers, surface coatings, and adhesives (5, 6).
It has been estimated that the production of TDI will steadily increase during the future years.
5.2 Diisocyanates are irritants to eyes, skin, and mucous membrane and are respiratory sensitizers. Chronic exposure to low
concentrations of diisocyanates produces an allergic sensitization which may progress into asthmatic bronchitis (7, 8).
5.3 The United States Occupational Safety and Health Administration (OSHA) has a permissible exposure limit (PEL) for
2,4-TDI of 0.02 ppm or 0.14 mg/m as a ceiling limit. There is no OSHA PEL for 2,6–TDI2,6-TDI (9). The American Conference
of Governmental Industrial Hygienists (ACGIH) has a time–weighted average (TWA) Threshold Limit Value (TLV) of 0.0050.001
3 3
ppm or 0.0360.007 mg/m and a short-term exposure limit (STEL) of 0.020.005 ppm or 0.140.036 mg/m for either
2,4–TDI,2,4-TDI, or 2,6–TDI,2,6-TDI, or for a mixture of 2,4–2,4- and 2,6–TDI2,6-TDI (10).
5.4 This proposed test method has been found satisfactory for measuring 2,4 and 2,6-TDI levels in the workplace.
6. Interferences
6.1 Any compound having the same retention time as the standards is a possible interference. Generally, chromatographic
conditions can be altered to resolve an interference.
6.2 Compounds that can react with an isocyanate represent a potential interference. These would include molecules containing
the functional groups: amines, alcohols, anhydrides, phenols, and carboxylic acids.
6.3 Strong oxidizing agents can potentially react with the 1-(2-pyridyl)piperazine.
6.4 Retention time data on a single column is not definitive proof of chemical identity. Analysis by an alternate column system,
ratioing of wavelength response using two wavelengths or types of detector, should be performed to confirm chemical identity.
7. Apparatus
7.1 Sampling Equipment:
7.1.1 Personal Sampling Pumps, any pump capable of sampling at a rate of about 1.0 L/min for 8 h.
7.1.2 Flowmeter, portable, with an accuracy that is sufficient to enable the volumetric flow rate to be measured to within 65 %.
The flowmeter calibration by a provider accredited to ISO/IEC 17025 for such calibrations shall be traceable to national or
international standards. Retain the calibration certificate, including the pressure and temperature at which the calibration was
performed, and identifying and performance documentation for the flowmeter.
,
7.1.3 Glass-Fiber Filters, 37 mm, free of organic binder, impregnated with 1.0 mg of 1-(2-pyridyl)piperazine.
7.1.4 Cassette, plastic holders of the three-piece personal monitor type, that accept filters of 37-mm diameter. Number the
cassette for identification.
7.1.5 Cellulose Backup Pad, sized to fit the cassette (7.1.37.1.4).
ORBO-80 filters supplied by Supelco, Inc., Bellefonte, PA have been found satisfactory for this purpose.Available from International Organization for Standardization
(ISO), ISO Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, http://www.iso.org.
D5836 − 20
7.1.6 (Optional) Glass Vial, fitted with polytetrafluoroethylene (PTFE)-lined caps, containing 4.0-mL of extraction solution
(8.6). Number the vial for identification.
7.2 Analytical Equipment:
7.2.1 Liquid Chromatograph, a high-performance liquid chromatograph (HPLC) equipped with a fluorescence detector capable
of monitoring 240-nm excitation and 370-nm cutoff or a UV detector capable of monitoring 254-nm wavelength and a manual or
automatic sample injector. A second UV wavelength is recommended for identify confirmation if no fluorescence detector is
utilized. An ultra high performance liquid chromatography (UPLC) providing at least the same or equivalent performance of HPLC
can be also used.
7.2.2 Liquid Chromatographic Column, an HPLC stainless steel column capable of separating the urea derivatives. Analytical
columnscolumn recommended in this test method are the following: a 25-cm by 4.6-mm inside diameter stainless steel column
packed with 10-μm Alltech C8; 6-μm Zorbax CN ; 5-μm Zorbax TMS; 5-μm Chromegabond TMS; 5-μm Spherisorb C6; 5-μm
Supelcosil LC-CN; or an equivalent column.
7.2.3 Electronic Integrator, an electronic integrator or some other suitable method of determining peak areas or heights.
7.2.4 Pipets and Volumetrics, various sizes of volumetric pipets and flasks to prepare standards.
7.2.5 Syringe Operated Filter Unit, syringes with 4 mm, polyvinylidene fluoride 0.2-μm pore size filter unit, or any equivalent
device.
7.2.6 HPLC Autosampler Vials, amber glass vials with a 4-mL volume and fitted with polytetrafluoroethylene-lined caps used
for extraction of samples.PTFE-coated septums.
7.2.7 Reciprocating Shaker, a reciprocating shaker or any other equivalent device.
8. Reagents and Materials
8.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. It is intended that all reagents shall conform to the
specifications of the Committees on Analytical Reagents of the American Chemical Society, where such specifications are
available. Other grades may be used provided it can be demonstrated that they are of sufficiently high purity to permit their use
without decreasing the accuracy of the determination.
8.2 Purity of Water—Unless otherwise indicated, reference water shall be understood to mean Type II reagent water conforming
to Specification D1193, HPLC grade.
8.3 Acetonitrile (CH CN)—HPLC grade.
8.4 Ammonium Acetate (CH COONH )—HPLC grade.
3 4
8.5 Dimethyl Sulfoxide ((CH ) SO)—HPLC grade.
3 2
8.6 Extracting Solution—A solvent mixture of acetonitrile and dimethyl sulfoxide in the percentage of 90 and 10 (v/v),
respectively.
8.7 Glacial Acetic Acid (CH COOH)—Reagent grade.
8.8 Hexane (C H )—HPLC grade.
6 14
8.9 Methylene Chloride (CH Cl )—HPLC grade.
2 2
8.10 Mobile Phase—A solvent mixture of acetonitrile (8.3) and water in the percentage of 37.5 and 62.5 (v/v), respectively. Add
to the mobile phase enough ammonium acetate (8.4) (1.54 to 7.7 g/L of solution or 0.02 to 0.1 N) to optimize the chromatographic
resolution. Add acetic acid (8.7) to the mixture to lower the pH to 6.0 to 6.2.
8.11 1-(2-Pyridyl)piperazine (1-2 PP) (C H N )—Reagent grade.
9 13 3
8.12 N,N'-(4-Methyl-1,3-phenylene)bis [4-(2-pyridinyl)-1-piperazinecarboxamide] (C H N O )—(2,4-TDIP).
27 32 8 2
8.13 N,N'-(2-Methyl-1,3-phenylene)bis [4-(2-pyridinyl)-1-piperazinecarboxamide] (C H N O )—(2,6-TDIP).
27 32 8 2
8.14 2,4-Toluene Diisocyanate (C H N O )—Reagent grade.
9 6 2 2
8.15 2,6-Toluene Diisocyanate (C H N O )—Reagent grade.
9 6 2 2
Isocyanate glass fiber filters supplied by Forest Biomedical, Salt Lake City, UT, have been found satisfactory for this purpose.
10-μm ALLTECH C8 supplied by Alltech Associates, Deerfield, IL, has been found satisfactory for this purpose.
6-μm ZORBAX CN and 5-μm ZORBAX TMS supplied by E.I. DuPont, Wilmington, DE, have been found satisfactory for this purpose.
5-μm Chromegabond TMS supplied by ES Industries, Marlton, NJ, has been found satisfactory for this purpose.
5-μm Spherisorb C6 supplied by PhaseSep, Hauppauge, NY, has been found satisfactory for this purpose.
5-μm Supelcosil LC-CN supplied by Supelco, Inc., Belleforte, PA has been found satisfactory for this purpose.
Reagent Chemicals, American Chemical Society SpecificationsACS Reagent Chemicals, Specifications and Procedures for Reagents and Standard-Grade Reference
Materials, , American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed by the American Chemical Society, see Analar Standards for
Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC),
Rockville, MD.
D5836 − 20
9. Safety Precautions
9.1 The diisocyanates are potentially hazardous chemicals and are extremely reactive. Avoid exposure to the diisocyanate
standards. Sample and standard preparations should be done in an efficient operating hood.
9.2 Avoid skin contact with diisocyanates and all solvents.
9.3 Wear safety glasses at all times and other laboratory protective equipment as necessary.
9.4 Safety data sheets (SDS) shall be consulted accordingly.
10. Sampling
10.1 Refer to Practices D1357 and D3686 for general information on sampling.
10.2 Adjust the personal sampling pumps to the recommended flow rate with an assembled cassette between the pump and the
flow-measuring device in accordance to Practice D5337. After the sampling, perform a post sampling flow rate verification. If the
post sampling flow rate varies more than 65 % from the recommended flow rate, invalidate the sample
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