ASTM E3325-21 - Standard Practice for Sampling of Solar Photovoltaic Modules for Toxicity Testing
Standard Practice for Sampling of Solar Photovoltaic Modules for Toxicity Testing
| Standard number: | E3325-21 |
| Released: | 01.11.2021 |
| Status: | Active |
| Pages: | 11 |
| Section: | 12.02 |
| Keywords: | disposal; lead; PV module; recycling; sampling; solar photovoltaic module; toxicity; |
1.1 The purpose of this practice is to describe a representative and repeatable sample preparation methodology to conduct toxicity testing on solar photovoltaic (PV) modules for use with EPA Test Method 1311: Toxicity Characteristic Leaching Procedure (TCLP).
1.2 This practice refers to the extraction and preparation of PV module samples by EPA Method 1311, the testing for eight (8) distinct metals – mercury (by Method 7470A), arsenic, barium, cadmium, chromium, lead, selenium and silver (by Method 6010C) as well as the analysis and interpretation of the test results on a module level.
1.3 This practice applies to only (1) standard crystalline silicon (c-Si) modules, multi and mono-crystalline silicon with aluminum back surface field (Al-BSF) cell technology and (2) cadmium telluride (CdTe) PV modules.
1.4 Other and newer PV technologies and module architectures, for example, passivated emitter and rear cell (PERC), interdigitated back contact (IBC), hetero-junction technology (HJT), multiwire, half cut, shingled etc., have not been evaluated with this practice, although the concept and practice can be easily extended and applied to other technologies following the conceptual approach presented in this document.
1.5 The sample extraction/removal methodology applied in this practice is the waterjet cutting sampling method. Sample extraction with mechanical cutting has been extensively evaluated but the variability of TCLP test results based on the mechanical cut samples tend to be much higher (30 %) than that of the waterjet cut samples (8 %).2 Therefore, the mechanical cut method is not presented in this practice.
1.6 Only the laminate area of the PV module is considered for TCLP testing, as other possible module parts, such as aluminum frame, junction box and cables contain recyclable materials that are already well-documented and are not specific to the PV modules.
1.7 The material gravimetric density (g/cm3) throughout the laminate area is considered constant.
1.8 This practice was developed to be consistent with three fundamental requirements:
1.8.1 Sample pieces with particle size not to exceed the allowed size limit of EPA 1311 standard which is 9.5 mm,
1.8.2 The particle size used in this practice as sample piece is consistent with the median particle size expected in landfill disposal2, and
1.8.3 An assumption that each laminate sample piece will result in 100 % glass coverage area, due to the presence of bonding encapsulant layers once it is broken in the landfill.
1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.10 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.
1.11 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.