I work on many projects where IFC is a required deliverable.
In order to produce well structured IFC (using the dreaded R word) we hard code all Ifc entity types and entity type enumerations into our object libraries. We have developed tools which then allow us to select any Ifc associated pset property to any object.
Often we come across objects (items of plant & equipment etc) that don’t have a corresponding IFC entity type.
On a current project there are a whole class of equipment items that don’t have any suitable IFC representation. Could I suggest that the following Ifc entity types are considered for inclusion in a future Ifc version
IfcLaboratoryEquipmentType
(example enum types FUMECUPBOARD, CONTAINMENTISOLATOR, SCANNER, LABORATORYREFIGERATOR, ELECTRONMICROSCOPE etc etc)
IfcMedicalEquipmentType
(example enum types XRAYSCANNER, MRISCANNER, CATSCANNER, SURGERYLAMP etc etc)
I would leave it up to the developers as to where such types would sit in the Ifc hierarchy, but there would most likely need to be corresponding psets for each equipment type.
Hi!
There is a limit to how much you can standardise in IFC and expect all software to support it properly.
IFC has a mechanism to ‘extend’ the standard with user defined properties, object types and additional classifications ( and references).
You can do this using the IfcClassificationReference mechanism, or the ObjecType mechanism. Some examples can be found here: Léon van Berlo - Technical Update on Vimeo
When you have returning ‘extensions’ that you want to ‘standardise’ and re-use in multiple projects you can create that as well and publish those.
This is where the buildingSMART Data Dictionary (bSDD - buildingSMART Data Dictionary - buildingSMART International) could come in. For example when you have a set of classes extending (further specialising) IFC classes you can publish those in the bSDD and add properties to them. You can also link/add properties from other standards (like IFC) to those classes as well. More detailled info on how that works can be found here: Frédéric Grand - bSDD on Vimeo
There is even a nice integration between bSDD and the ‘Information Delivery Specification’ (IDS) to balance more rigid standards with more agile project requirements. But that is probably a step too far for this comment.
Please don’t hesitate to reach out. I’m not really good with the forum but you can always reach me on leon.vanberlo@buildingsmart.org