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Glossary

collaboration server
An openLCA specific server application, maintained by GreenDelta, that allows users to work collaboratively on LCA models, share data, and host public LCA repositories such as those available on lcacommons.gov. For more information, see GreenDelta’s Collaboration Server.
context
In the case of the FEDEFL (and often in LCA more broadly), context describes the origin or destination of an elementary flow. Context informs the directionality of an elementary flow. Resource flows are extracted from nature, while emissions are released to nature. List of FEDEFL contexts. For more discussion of context see EPA’s FEDEFL Report
cut-off flow
a flow that is a placeholder or a dummy flow. These flows are used when no relevant flows in a database exists. It is not recommended to use these flows in your life cycle inventory if possible. In openLCA results, cut-off flows will appear in your inventory results, but will not contribute to impact category results.
data package
“A simple container format for describing a coherent collection of data in a single ‘package’. It provides the basis for convenient delivery, installation and management of datasets.” from datapackage.org
Disability-Adjusted Life Years (DALY)
“One DALY represents the loss of the equivalent of one year of full health. DALYs for a disease or health condition are the sum of the years of life lost to due to premature mortality (YLLs) and the years lived with a disability (YLDs) due to prevalent cases of the disease or health condition in a population.” from World Health Organization
elementary flow
A material (resource), energy, or space that is exchanged with the biosphere. An elementary flow is characterized by a unique combination of flowable and context information and is assigned a UUID.
endpoint indicator
A category of LCIA indicator that expresses characterized impact in terms of damage caused to an area of concern such as the natural environment, human health or resource supply. An example of an endpoint indicator would be the human health impact of particulate matter formation potential expressed in Disability-Adjusted Life Years (DALY).
exchange
a quantity of a flow that is moved into or out of a process. Exchanges are reflected as individual rows in the Inputs/Outputs tab of a process.
Environmental Product Declaration
A third-party verified report of the environmental impacts of a product. EPDs are developed according to ISO 14025 and the relevant ‘product category rule’ for that product type. For more information see the FHWA EPD Tech Brief
Federal Elementary Flow List
The Federal Elementary Flow List (FEDEFL) is a standardized list of elementary flow names, developed by the U.S. Environmental Protection Agency, used in federal LCA work. See the EPA Report on its development and use.
flow
“Flows are the essential components of data used for LCA. Flows may be of two broad types: elementary flows or intermediate (known as "technosphere") flows.” from EPA’s FEDEFL Report
flowable
A general term for the name of a material, energy or space that is exchanged with the biosphere. For more discussion of flowables see EPA’s FEDEFL Report
functional unit
The reference unit of a product system within LCA. Results are run and compared on the functional unit. ISO 14040
International Organization for Standardization
An independent, non-governmental body with members from national standards boards that develops standard procedures for technical processes, such as life cycle assessment.
JSON-LD
a file format used by openLCA and the collaboration server for transferring data objects. JSON-LD objects should not be unzipped when importing into openLCA.
Life Cycle Assessment
United Nations description of environmental LCA
library
A type of data package limited to read-only access, intended to serve as a dependency of another data package. The library feature in openLCA 2.0 and later versions enables the use of databases together without the need to import them on top of one another. Processes and other elements that are part of a library database are not editable but can be utilized as part of processes or product systems in the main database.
midpoint indicator
“A characterization method that provides indicators for comparison of environmental interventions at a level of cause-effect chain between emissions/resource consumption and the endpoint level.” from the European Commission report Indicators and targets for the reduction of the environmental impact of EU consumption: Overall environmental impact (resource) indicators. A common example of a midpoint indicator is global climate change potential where impacts are expressed as kg CO2equivalents.
parquet
an open source file format for tabular data that minimizes storage space.
process
A set of related activities that convert inputs into output(s). A network of processes, the product system, is used to define the life cycle of a product. Processes are characterized as unit processes or system processes. For more discussion of processes see openLCA 2 manual
Product Category Rule
A collection of data source, scoping, and allocation rules for an Environmental Product Declaration. “A set of specific rules, requirements and guidelines for developing Type Ill environmental declarations for one or more product categories.” fromISO 14025. See also EPA’s Guidance for Product Category Rule Development
product flow
These are all the flows that are not elementary or waste flows, and represent the materials or energy exchanged between processes within the product system. openLCA 2 manual
product system
“A collection of unit processes with elementary and product flows, performing one or more defined functions, and which models the life cycle of a product.” -from openLCA 2 manual
provider
A provider in openLCA is the upstream process that produces a flow. Providers can be chosen in the ‘Inputs/Outputs’ tab in openLCA under the ‘Provider’ column for product and waste flows. Read more about openLCA provider linkages in the openLCA manual here.
repository
A remote or local container in which data are stored under version control, from which a release of contained data can be published. The term repository is often applied to individual data releases (e.g. USLCI) on the collaboration server or individual GitHub sites (e.g. FLCAC-docs.
resource flow
A material or energy flow exiting the biosphere, which serves as an LCA process input.
system process
“An aggregated life cycle result saved as a process.” -from openLCA 2 manual
technosphere flow
Intermediate product or service flows that serve as inputs to subsequent processes or comprise the functional unit of a product system.
unit process
“The smallest (least aggregated) unit in a production system, for which input and output data are quantified.” -from openLCA 2 manual
UUID
Universally Unique Identifiers. Unrepeated alphanumeric code that points to specific database objects, typically within a JSON file. Within openLCA, UUIDs are assigned to processes, flows, product systems, projects, parameters, impact categories and LCIA methods. Link to UUID search in the openLCA 2 manual
waste flow
Waste flows are any substances or objects that the holder needs to dispose of, like by-products with no market value or those requiring more resources to recycle than their economic return. openLCA 2 manual