Bo is right, I looked at the ecospold2 source files to refresh my memory and they indeed call their master data elementary exchanges and intermediate exchanges. So it is actually only in the ILCD format that they do make the distinction between the flow-objects that they call flows and the flows that they call exchanges. And ILCD is confusing as well, as their flows are from both the technosphere and nature (so some have compartments while others don’t). So steel is a flow, as well as Carbon dioxide. That’s not very obvious, and I would say that by themselves, as we would like to consider them, they are not ‘flowing’ anywhere.
At PRé we haven’t come up with anything so far that covers all possible flow-objects. In the platform, we have a two types: substances and products. But the fact that they are separate and that substances also include things like labour and land use indicate that they aren’t the best solution either.
That was a bit of thinking out loud, not sure it is very helpful but it indicates that it has been a struggle for quite a few people already.
Back to what Bo suggested, intuitively flow-item sounds a bit better to me. Given the breath of things we want to cover with the term, there’s probably not much that sounds less abstract. But if someone comes up with a term that sounds a bit more friendly, I’m interested.
email@example.com [mailto:firstname.lastname@example.org] On Behalf Of Bo Weidema
The important issue is to distinguish between the observation of a specific flow (e.g. 22 kg input of steel) and the abstract flow-object ("steel"). This distinction was not made clear in e.g. ecospold schema where the exchange = flow and the abstract flow-object is simply called "intermediateExchangeId" or "elementaryExchangeId" referring to a taxonomy of "master data".
I do not think it makes much difference if we call it flow-object or flow-item, so if there is a preference for the latter that would be OK with me. Exchange has the problem that it is easily confused with a market operation (e.g. currency exchange). So I think "flow" is still the best option, as this is either an input or an output.