94
data points. A manufacturer may turn this type of information flow into a freely
available continually published dataset or may choose to keep it for internal uses
only. Not all US states require regular monitoring and reporting on point source
discharges produced by industry and those that do concentrate on sectors and individual plants that have the potential to produce them over a certain threshold. New
Jersey, for instance, sets thresholds for reporting on air emissions at or above 10
tons per year of volatile organic compounds (VOCs), 25 tons per year of nitrogen
oxide (NOx), and 100 tons each per year of ammonia, carbon monoxide (CO), sulfur dioxide (SO 2 ), particulate matter 10 micrometers (PM10), or particulate matter
2.5 micrometers (PM2.5) (NJDEP 2018).
LCA professionals with access to a manufacturer’s granular emissions, effluent,
and solid waste inventory data can eventually evaluate and recommend improvements to foreground unit processes or subprocesses. Continuous improvement can
be gauged against internal or external benchmarks, but all are driven by data quantity and quality.
In some cases, identifying and validating hotspots in LCI data and relating them
to a functional unit’s reference flows comprise a full study in its own respect.
Straightforwardly called an LCI study ISO 14040 (2006a), it is generally distinguished from a full LCA by its lack of an impact assessment phase. LCI studies can
provide designers and other decision-makers with insight into materials and processes with higher or lower recorded values over a range of inputs or outputs
although, regardless of the data quality and quantity, they cannot be the sole determinant in making a final choice between two options. The goal and scope establishes initial data quantity and quality parameters and the need to go beyond an LCI
to produce a complete LCA.
5.3.10 What Data Assumptions Apply to the Study?
Each study or model is an abstraction and simplification of a much more complex
reality. Numerous foundational assumptions bracket and limit what the model can
appropriately represent. This applies equally to the most complex global climate
models as it does to a digital simulation of a small paper cup. Each LCA functional
unit typically describes a material quantity, a specific purpose the unit will serve,
and a service life period. Definitions and specifications of the materials and processes that make up the product system support qualified conclusions about a study
especially when comparing it to other studies or when comparing product systems
within a single LCA.
Some studies will focus only on a portion of the system’s life cycle. This could
be cradle to gate, a single gate to gate, gate to grave, and span multiple gates, or it
could encompass the entire cradle to grave/cradle life cycle. Since many types and
sources of data may be used, best practice requires qualifying assumption statements about information quality and breadth and its appropriateness to the life cycle
segment under review.
5 Life Cycle Assessment
data points. A manufacturer may turn this type of information flow into a freely
available continually published dataset or may choose to keep it for internal uses
only. Not all US states require regular monitoring and reporting on point source
discharges produced by industry and those that do concentrate on sectors and individual plants that have the potential to produce them over a certain threshold. New
Jersey, for instance, sets thresholds for reporting on air emissions at or above 10
tons per year of volatile organic compounds (VOCs), 25 tons per year of nitrogen
oxide (NOx), and 100 tons each per year of ammonia, carbon monoxide (CO), sulfur dioxide (SO 2 ), particulate matter 10 micrometers (PM10), or particulate matter
2.5 micrometers (PM2.5) (NJDEP 2018).
LCA professionals with access to a manufacturer’s granular emissions, effluent,
and solid waste inventory data can eventually evaluate and recommend improvements to foreground unit processes or subprocesses. Continuous improvement can
be gauged against internal or external benchmarks, but all are driven by data quantity and quality.
In some cases, identifying and validating hotspots in LCI data and relating them
to a functional unit’s reference flows comprise a full study in its own respect.
Straightforwardly called an LCI study ISO 14040 (2006a), it is generally distinguished from a full LCA by its lack of an impact assessment phase. LCI studies can
provide designers and other decision-makers with insight into materials and processes with higher or lower recorded values over a range of inputs or outputs
although, regardless of the data quality and quantity, they cannot be the sole determinant in making a final choice between two options. The goal and scope establishes initial data quantity and quality parameters and the need to go beyond an LCI
to produce a complete LCA.
5.3.10 What Data Assumptions Apply to the Study?
Each study or model is an abstraction and simplification of a much more complex
reality. Numerous foundational assumptions bracket and limit what the model can
appropriately represent. This applies equally to the most complex global climate
models as it does to a digital simulation of a small paper cup. Each LCA functional
unit typically describes a material quantity, a specific purpose the unit will serve,
and a service life period. Definitions and specifications of the materials and processes that make up the product system support qualified conclusions about a study
especially when comparing it to other studies or when comparing product systems
within a single LCA.
Some studies will focus only on a portion of the system’s life cycle. This could
be cradle to gate, a single gate to gate, gate to grave, and span multiple gates, or it
could encompass the entire cradle to grave/cradle life cycle. Since many types and
sources of data may be used, best practice requires qualifying assumption statements about information quality and breadth and its appropriateness to the life cycle
segment under review.
5 Life Cycle Assessment