1、Designation: D7788 14Standard Practice forCollection of Total Airborne Fungal Structures via InertialImpaction Methodology1This standard is issued under the fixed designation D7788; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 The purpose of this practice is to describe procedures forthe collection of airborne fungal spores or fragm
3、ents, or both,using inertial impaction sampling techniques.1.2 This practice is not intended to limit the user from thecollection of other airborne particulates that may be of interestand captured through this technique.1.3 This practice presumes that the user has a fundamentalunderstanding of field
4、 investigative techniques related to thescientific process, and sampling plan development and imple-mentation. It is important to establish the related hypothesis tobe tested and the supporting analytical methodology needed inorder to identify the sampling media to be used and thelaboratory conditio
5、ns for analysis.1.4 This practice does not address the development of aformal hypothesis or the establishment of appropriate anddefensible investigation and sampling objectives. It is pre-sumed the investigator has the experience and knowledge baseto address these issues.1.5 This practice does not p
6、rovide the user sufficient infor-mation to allow for interpretation of the analytical results fromsample collection. It is the users responsibility to seek orobtain the information and knowledge necessary to interpretthe sample results reported by the laboratory.1.6 The values stated in SI units are
7、 to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices
8、and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD3195/D3195M Practice for Rotameter CalibrationD4840 Guide for Sample Chain-of-Custody ProceduresD6044 Guide for Represe
9、ntative Sampling for Managementof Waste and Contaminated MediaD7391 Test Method for Categorization and Quantification ofAirborne Fungal Structures in an Inertial ImpactionSample by Optical Microscopy3. Terminology3.1 DefinitionsFor definitions and terms not listed here,see Terminology D1356.3.1.1 in
10、ertial impactor, na device designed for the impac-tion of particles that are separated from the air stream by inertiaonto a collection surface. D73913.1.1.1 DiscussionInertial impactors are available inmany designs including “slit” and “circular” jets.3.1.1.2 DiscussionAllows for the identification
11、to genusor group of fungi detected, quantification to spores/m3, andgeneral assessment of background debris. Identification ofpollen, hyphal fragments and other airborne particulate may beincluded.3.1.2 sample, na portion of a population. A portion ofmaterial that is taken for testing or record purp
12、oses. D60443.1.3 sample, representative, na sample collected in sucha manner that it reflects one or more characteristics of interest(as defined by the project objectives) of a population fromwhich it is collected. D60443.1.3.1 DiscussionPopulations of airborne fungal sporesare typically not homogen
13、eous.3.2 Definitions of Terms Specific to This Standard:3.2.1 aerodynamic diameter (da), nthe diameter of a unitdensity sphere having the same inertial properties as theparticle under analysis under the same conditions.1This practice is under the jurisdiction of ASTM Committee D22 on Air Qualityand
14、is the direct responsibility of Subcommittee D22.08 on Sampling and Analysisof Mold.Current edition approved June 1, 2014. Published July 2014. DOI: 10.1520/D7788-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual B
15、ook of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1.1 DiscussionFor fungal spores this is generallybased on a water droplet, (s
16、pherical particle) having a densityof 1 g/cm3. Aerodynamic diameter has been developed tocategorize the sizes of particles of different shapes and densi-ties with a single dimension. The aerodynamic diameter is notnecessarily equal to the physical diameter due to variations inshape or density.3.2.2
17、calibration impactor, na designated cassette, ormedia unit, placed in the sampling assembly during calibrationor verification of the air flow rate.3.2.3 chain of custody (COC) record, na document thatprovides for the traceable transfer of field samples to theanalytical laboratory. It may or may not
18、be combined with thefield data sheet.3.2.3.1 DiscussionAdditional guidance can be found inGuide D4840.3.2.4 collection or capture effciency, nthe percentage of aspecified substance retained by a sampling device.3.2.4.1 DiscussionCollection or capture efficiency is afunction of the geometries of the
19、impactors and the air flowrate, the jet dimensions and jet to plate distance, and theaerodynamic diameters, shape, density and surface morphol-ogy of the airborne particles.3.2.5 field data sheet, na record that provides a referencedocument for information directly related to the sample col-lection
20、event, including pre- and post-calibration data.3.2.6 fungal structure (sing.), na collective term for frag-ments or groups of fragments from fungi, including but notlimited to conidia, conidiophores, hyphae and spores.3.2.7 fungus (sing.), fungi, (pl.), neukaryotic,heterotrophic, absorptive organis
21、ms that usually develop arather diffuse, branched, tubular body (that is, network ofhyphae) and usually reproduce by means of spores (1).3Theterms mold and mildew are frequently used by laypersonswhen referring to various fungal colonization.4. Significance and Use4.1 This practice is intended for t
22、he collection of airbornefungal spores or fragments, or both, using inertial impaction.4.2 It is the responsibility of the user to assure that they arein compliance with all local, state and federal regulationsgoverning the inspection of buildings for fungal colonizationand the collection of associa
23、ted samples.4.3 This practice is intended to provide the user with a basicunderstanding of the equipment, materials and instructionsnecessary to effectively collect air samples using an inertialimpactor.4.4 This practice, when properly executed, may also be usedfor the evaluation of other types of a
24、irborne particles with thecapturing characteristics appropriate for inertial impactor, andfor which appropriate analytical methods exist. Such particlesmay include dust mites, skin cells, pollen, and other materials.5. Preparation of Sampling Equipment5.1 Equipment List:5.1.1 Sampling AssemblyThe co
25、mbination of componentsfrom the pump/fan system through to the sampling media (forexample cassette, slide) including any transport tubing, flowcontroller and connectors. The configuration may be an inte-grated assembly or components that have been configured withan external pump/fan.NOTE 1Rotary van
26、e, diaphragm, linear magnetic, piston and fandriven devices may have the open flow capacity for specific impactors;however, resistance to flow through the impactor can dramatically reduceflow rates. Care must be taken to select a pump and calibrator that arecompatible with impactors to set and measu
27、re flow rates properly.5.1.1.1 Use an inertial impactor with a d50collection effi-ciency less than or equal to a 3.0 m dain accordance with themanufacturers recommended flow rate, sample time, andsample orientation. Record these parameters.NOTE 2Use collection efficiency data available from manufact
28、urerstechnical reports or from peer-reviewed published data.NOTE 3All bioaerosol impactors operate on the same principlesregardless of the operating parameters. However, all impactors are notequally effective or efficient in trapping particles from an air stream.Published data investigating some com
29、mon fungi in airborne samplesdiscusses these differences and how they affect collection efficiency (2-5).5.1.1.2 For external pump/fan assemblies, use flexible tub-ing and connectors appropriate for secure connection ofimpactor to pump/fan.5.1.2 Primary flow calibration device with a measuringrange
30、appropriate for the system and with a 65 % tolerance ofthe desired flow rate.5.1.3 Secondary flow calibration or verification device, forexample, rotameter or other device used to check systemperformance in the field.5.1.4 Stop watch or other timing device capable of measur-ing time in increments of
31、 minutes and seconds (one secondresolution).5.1.5 Field data sheet. Refer to 6.6.5.1.6 Support stand (optional). Allows for consistentsample collection height.5.2 Assembly Calibration:5.2.1 Calibrate or verify airflow through the assemblyconfiguration that will be used in the field. For example, do
32、notcalibrate with one length of tubing and sample with a differentlength of tubing.5.2.2 Use a primary or a calibrated secondary flow device toverify the airflow rate passing through the sampling assembly.The investigator should be aware that it is the airflow ratethrough the impactor, not the pump/
33、fan that shall be calibrated.5.2.3 Verify the secondary flow device using a primarycalibration device in accordance with the manufacturers rec-ommendations.5.2.4 Integrated sampling assemblies may not be capable ofbeing calibrated by the user. Follow manufacturers instruc-tions when user calibration
34、 is not possible.5.2.5 Verify and record the airflow prior to and followingfield sampling. If the result of the post-field verification checkis greater than 610 % of pre-field verification, either (1)discard any samples collected, re-adjust the sampler as3The boldface numbers in parentheses refer to
35、 a list of references at the end ofthis standard.D7788 142necessary, and re-sample; or (2) note any airflow rate variationsin the field notes and any data interpreting documents, record-ing the magnitude of the change and averaging the airflow rates(Practice D3195/D3195M). Use this average airflow r
36、ate tocalculate sample volume.6. Sample Collection6.1 Preliminary Considerations:6.1.1 Inspect the collection media and discard any that aredamaged, expired, or compromised.6.2 Sample Position and Conditions:6.2.1 Position inertial impactor to allow the free flow of airaround it.6.2.2 Record samplin
37、g conditions including time, date, andlocation. If relevant, record other conditions such as;temperature, relative humidity, air movement (that is, wind,fans, HVAC), height above ground, and occupant activityduring sample collection.6.3 Sampling Time:6.3.1 Record the sampling time in minutes and sec
38、onds.6.3.2 Sampling time is determined by the manufacturersrecommendation and professional judgment.6.4 Sample Labeling:6.4.1 Label each sample with a unique identifier. Mediamanufacturers unique number (for example, serial number)may be used.6.4.2 Record sample unique identifier on a field sheet,lo
39、gbook, or chain of custody (COC) record, or combinationthereof.6.5 Sample Orientation:6.5.1 Follow manufacturers recommendations.6.6 Field Data Sheet:6.6.1 Record the following on the field data sheet:6.6.1.1 Sampling date,6.6.1.2 Project name and project location(s),6.6.1.3 Investigators name(s),6.
40、6.1.4 Type of sampling assembly,(1) Assembly pump/fan identifier may be appropriate.6.6.1.5 Pre- and post-verification data,6.6.1.6 Unique sample identifiers,6.6.1.7 Sample locations,6.6.1.8 Sampled air flow rate,6.6.1.9 Sample start time,6.6.1.10 Sample stop time or duration,6.6.1.11 Calculated sam
41、ple volume, and6.6.1.12 Environmental sampling conditions (refer to 6.2.2).6.7 Sampling Assembly Operation:6.7.1 Prepare the sampling assembly.6.7.2 Remove and maintain control of any protective coversfor the media and install media in the sampling assembly.6.7.3 Start pump/fan and record start time
42、 or duration whereoperation is on a timer.6.7.4 After sampling, turn pump/fan off and record stoptime.6.7.5 Reseal the media, with the protective covers if any,and remove from system.NOTE 4Use of timers may be helpful when operating multiplepump/fans simultaneously.NOTE 5Minimize influence on the sa
43、mple collection from operatorproximity to the sample inlet.6.8 Sample Submittal for Analysis:6.8.1 Submit samples for analysis with COC.6.8.2 The COC includes:6.8.2.1 Name and signature of investigator;6.8.2.2 Date, time, and signature of releasing party;6.8.2.3 Name and contact information of respo
44、nsible party(that is, investigators employer);6.8.2.4 Project identification (that is, project identifier orsite location, or both); and6.8.2.5 List of all samples being submitted.6.8.3 Communicate the following analytical request infor-mation:6.8.3.1 Contact information for analytical report receip
45、t, ifdifferent than submitters information;6.8.3.2 Analytical method requested (that is, Test MethodD7391 or other applicable method);6.8.3.3 Turn-around time requested;6.8.3.4 Sample volume or sample time and flow rate; and6.8.3.5 Special or unique instructions, if applicable.6.8.4 Sample transport
46、 for analysis.6.8.4.1 Protect samples from damage and temperature ex-tremes.6.8.4.2 Ship samples with a trackable carrier or hand de-liver.7. Interferences and Limitations7.1 The investigator must understand the purpose of theproject and consider interferences and limitations. Predictableand unpredi
47、ctable errors associated with sampling methodsexist.7.1.1 Predictable errors include, but are not limited tocollection efficiency, system design variations (Guide D6044).7.1.2 Unpredictable errors include, but are not limited toinherent variation in the concentration of airborne fungalstructures, ch
48、anges in environmental conditions, equipmentmalfunction, etc.7.2 The collection efficiency of the system may be affectedby extremes in temperature, relative humidity, atmosphericpressure, wind speed, and direction.7.3 The overall effectiveness and collection efficiency of aninertial impaction sample
49、r is a function not only of systemdesign and operation but also of fungal structure size, density,morphology (shape and roughness), concentration, and theamount of non-fungal airborne debris. The investigator shouldbe aware that not all types and sizes of fungal structures areretained to the same degree by each system. Consult themanufacturer for specific information.8. Keywords8.1 aerodynamic diameter; bioaerosol; calibration; captureefficiency; collection efficiency; d50; fungal structure; fungi;fungus; hyphal fragment; impactor; indoor air qu
