1、Designation: E2535 07 (Reapproved 2018)Standard Guide forHandling Unbound Engineered Nanoscale Particles inOccupational Settings1This standard is issued under the fixed designation E2535; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the 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.INTRODUCTIONNanometre-scale particles are encountered in nature and in industry in a variety of forms andmaterial
3、s. Engineered nanoscale particles as a class comprise a range of materials differing in shape,size, and chemical composition, and represent a broad range of physical and chemical properties.Workers within some nanotechnology-related industries and operations have the potential to beexposed to these
4、engineered nanoscale particles at levels exceeding ambient nanoscale particleconcentrations through inhalation, dermal contact and ingestion when not contained on or within amatrix (unbound). Occupational health risks associated with manufacturing, processing and handlingunbound nanoscale particles,
5、 agglomerates, or aggregates of nanoscale particles are not yet clearlyunderstood. Dominant exposure routes, potential exposure levels and any material hazard are expectedto vary widely among particular nanoscale particle materials and handling contexts. Additionalresearch is needed to understand th
6、e impact of these exposures on employee health and how best todevise appropriate exposure monitoring and control strategies. Until clearer understandings emerge,the limited evidence available suggests caution when potential exposures to unbound engineerednanoscale particles (UNP) may occur.1. Scope1
7、.1 This guide describes actions that could be taken by theuser to minimize human exposures to unbound, engineerednanoscale particles (UNP) in research, manufacturing, labora-tory and other occupational settings where UNP may reason-ably be expected to be present. It is intended to provideguidance fo
8、r controlling such exposures as a cautionary mea-sure where neither relevant exposure standards nor definitivehazard and exposure information exist.1.2 General GuidanceThis guide is applicable to occupa-tional settings where UNP may reasonably be expected to bepresent. Operations across those settin
9、gs will vary widely inthe particular aspects relevant to nanoscale particle exposurecontrol. UNP represent a vast variety of physical and chemicalcharacteristics (for example, morphology, mass, dimension,chemical composition, settling velocities, surface area, surfacechemistry) and circumstances of
10、use. Given the range ofphysical and chemical characteristics presented by the variousUNP, the diversity of occupational settings and the unevenempirical knowledge of and experience with handling UNPmaterials, the purpose of this guide is to offer general guidanceon exposure minimization approaches f
11、or UNP based upon aconsensus of viewpoints, but not to establish a standardpractice nor to recommend a definite course of action to followin all cases.1.2.1 Accordingly, not all aspects of this guide may berelevant or applicable to all circumstances of UNP handling.The user should apply reasonable j
12、udgment in applying thisguide including consideration of the characteristics of theparticular UNP involved, the users engineering and otherexperience with the material, and the particular occupationalsettings where the user may apply this guide. Users areencouraged to obtain the services of qualifie
13、d professionals inapplying this guide.1.2.2 Applicable Where Relevant Exposure Standards DoNot ExistThis guide assumes that the user is aware of and incompliance with any authoritative occupational exposure stan-dard applicable to the bulk form of the UNP. This guide may beappropriate where such exp
14、osure standards do not exist, orwhere such standards exist, but were not developed withconsideration of the nanoscale form of the material.1.3 Applicable Where Robust Risk Information Does NotExistThis guide assumes the absence of scientifically soundrisk assessment information relevant to the parti
15、cular UNP1This guide is under the jurisdiction of ASTM Committee E56 on Nanotech-nology and is the direct responsibility of Subcommittee E56.03 on Environment,Health, and Safety.Current edition approved Oct. 1, 2018. Published October 2018. Originallyapproved in 2007. Last previous edition approved
16、in 2013 as E2535 07 (2013).DOI: 10.1520/E2535-07R18.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in th
17、e Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1involved. Where sound risk assessment information exists, orcomes to exist, any exposure control measures should bede
18、signed based on that information, and not premised on thisguide. Such measures may be more or less stringent than thosesuggested by this guide.1.4 Materials Within ScopeThis guide pertains to un-bound engineered nanoscale particles or their respirable ag-glomerates or aggregates thereof. Relevant na
19、noscale particletypes include, for example, intentionally produced fullerenes,nanotubes, nanowires, nanoropes, nanoribbons, quantum dots,nanoscale metal oxides, and other engineered nanoscale par-ticles. Respirable particles are those having an aerodynamicequivalent diameter (AED) less than or equal
20、 to 10 m (10 000nm) or those particles small enough to be collected with arespirable sampler (1-3).2The AED describes the behavior ofan airborne particle and is dependent upon the particle density,shape, and sizefor instance, a particle with a spherical shape,smooth surface, density of 1.0 g/cc and
21、a physical diameter of4 m would have an AED of 4 m, whereas a particle with aspherical shape, smooth surface, density of 11.35 g/cc and aphysical diameter of 4 m would have an AED of 14 m andwould therefore be of a nonrespirable size. Respirable fibersare those having physical diameters less than or
22、 equal to 3 m(3000 nm) or those fibers small enough to be collected with athoracic sampler (4, 5).1.5 Materials Beyond Scope:1.5.1 UNP may be present in various forms, such aspowders or suspensions, or as agglomerates and aggregates ofprimary particles, or as particles dispersed in a matrix. Thisgui
23、de does not pertain to UNP incapable, as a practical matter,from becoming airborne or be expected to generate or releaseUNP in occupational settings under the particular circum-stances of use (for example, UNPs dispersed or otherwise fixedwithin a solid, strongly bonded to a substrate or containedwi
24、thin a liquid matrix such as aggregated primary crystals ofpigments in paints). This guide does not pertain to aggregatesor agglomerates of UNP that are not of a respirable size.1.5.2 This guide does not pertain to materials that presentnanoscale surface features, but do not contain UNPs (forexample
25、, nanoscale lithography products, nanoelectronic struc-tures or materials comprised of nanoscale layers).1.5.3 This guide does not pertain to UNPs which exist innature which may be present in normal ambient atmospheres orare unintentionally produced by human activities, such as bycombustion processe
26、s. Nor does it pertain to materials thathave established exposure control programs (for example, safehandling protocols for nanoscale biological agents) or pub-lished exposure limits such as occupational exposure limits forwelding fumes. See Appendix X1.1.6 Handling Considerations Beyond ScopeThe us
27、e ofthis guide is limited to the scope set forth in this section. Thisguide generally does not address actions related to potentialenvironmental exposures, nor to exposures potentially arisingat disposal or other end-uses.1.7 Not a Standard of CareThis guide does not necessar-ily represent the stand
28、ard of care by which the adequacy of aset of exposure control measures should be judged; nor shouldthis document be used without consideration of the particularmaterials and occupational circumstances to which it may beapplied. The word “standard” in the title means only that thedocument has been ap
29、proved through the ASTM consensusprocess.1.8 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.9 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of th
30、e user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.10 This international standard was developed in accor-dance with internationally recognized principles on standard-ization establish
31、ed in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3E2456 Terminology Relating to NanotechnologyF1461 Practice for Chem
32、ical Protective Clothing Program3. Terminology3.1 DefinitionsRefer to Terminology E2456 for defini-tions of terms used within this guide.3.2 Definitions of Terms Specific to This Standard:3.2.1 aerodynamic equivalent diameter (AED), nthe di-ameter of a smooth, unit density o= 1 gram per cubiccentime
33、tre (g/cm3) sphere that has the same terminal settlingvelocity as the actual particle (6).3.2.2 agglomerate, nin nanotechnology, a group of par-ticles held together by relatively weak forces (for example, vander Waals or capillary.) and which may break apart into smallerparticles upon processing.3.2
34、.3 aggregate, nin nanotechnology, a discrete group ofparticles in which the various individual components are noteasily broken apart, such as in the case of primary particles thatare strongly bonded together (for example, fused, sintered, ormetallically bonded particles).3.2.4 control principle, nth
35、e principle establishes in thisguide that, as a cautionary measure, occupational exposures tounbound, engineered nanoscale particles (UNP) should beminimized to levels that are as low as is reasonably practicable.3.2.5 nanoscale, adjhaving one or more dimensions onthe order of 1 to 100 nanometres.2T
36、he boldface numbers in parentheses refer to the list of references at the end ofthis standard.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document
37、 Summary page onthe ASTM website.E2535 07 (2018)23.2.6 particle, nin nanotechnology, a small object thatbehaves as a whole unit in terms of transport and properties.3.2.7 program, na management policy to minimize occu-pational UNP exposures together with the procedures andactions to meet that object
38、ive.3.2.8 respirable, adjairborne particles which are smallenough to enter the alveolar (gas-exchange) region of the lung.3.2.9 inhalable, adjairborne particles which are smallenough to enter the head airways through the nose or mouth, orboth, during inhalation.3.2.10 should, aux., vas used in this
39、guide, indicates thata provision is not mandatory but is recommended as a goodpractice.3.2.11 ultrafine particle, na particle smaller than about 0.1micrometre (100 nanometres) in diameter.3.2.12 unbound, adjwith reference to engineered na-noscale particles, those nanoscale particles that are not con
40、-tained within a matrix under normal temperature and pressureconditions that would reasonably be expected to prevent theparticles from being separately mobile and a potential source ofexposure. An engineered primary nanoscale particle dispersedand fixed within a polymer matrix, incapable as a practi
41、calmatter of becoming airborne, would be “bound,” while such aparticle suspended as an aerosol would be “unbound.”3.3 Acronyms:3.3.1 HEPAhigh efficiency particulate air3.3.2 MSDSmaterial safety data sheet(s)3.3.3 PPEpersonal protective equipment3.3.4 UNPunbound engineered nanoscale particles4. Summa
42、ry of Guide4.1 This guide presents the elements of an UNP handlingand exposure minimization program including considerationsand guidance, based on a consensus of viewpoints, for estab-lishing such a program. The six principal elements are: (a)establishing management commitment to the control princip
43、le;(b) identifying and communicating potential hazards; (c) as-sessing potential UNP exposures within the worksite; (d)identifying and implementing engineering, and administrativecontrols consistent with the control principle for all relevantoperations and activities; (e) documentation; and (f) peri
44、odi-cally reviewing its adequacy.4.2 The Control PrincipleExposure control guidance inthis guide is premised on the principle (established in thisguide) that, as a cautionary measure, occupational exposures toUNP should be minimized to levels that are as low as isreasonably practicable. This princip
45、le does not refer to aspecific numerical guideline, but to a management objective,adopted on a cautionary basis, to guide the user when (a)assessing the site-specific potential for such exposures; (b)establishing and implementing procedures to minimize suchexposures; (c) designing facilities and man
46、ufacturing pro-cesses; and (d) providing resources to achieve the objective.Additional discussion of the application of the control principleis set forth in Annex A1.5. Significance and Use5.1 This guide is intended for use by entities involved in thehandling of UNP in occupational settings. This gu
47、ide covershandling principles and techniques that may be applied, asappropriate, to the variety of UNP materials and handlingsettings. These settings include research and developmentactivities, material manufacturing, and material use and pro-cessing. This guide may also be used by entities that rec
48、eivematerials or articles containing or comprising nanoscale par-ticles fixed upon or within a matrix (that is, bound nanoscaleparticles), but whose own processes or use may reasonably beexpected to cause such particles to become unbound.6. Establishing a Program to Implement the ControlPrinciple6.1
49、 Process for Establishing ProgramTo attain the inte-grated effort needed to minimize UNP exposures consistentwith the control principle, the user should develop a programthat addresses the efforts in all management, planning andoperational phases of the enterprise to be taken to achieve thatobjective. The principal topics of this guide outline an iterativeprocess typical of many occupational safety regimes the user ofthis guide may adopt for the initial establishment and imple-mentation of an effective program to minimize occupationalUNP exposures
