# Does SBOL support timing and threshold value parameters?

Like the propagation delay and threshold value parameters in electronic circuits, does SBOL format support any such parameters/glyph to represent the propagation delay (time to trigger the output protein once the input is provided) and threshold value (minimum input concentration required to trigger the model's output) of genetic models?

If currently not supported, can these parameters be incorporated in the SBOL visual representation which would give reader an idea (just by looking at the schematic diagram) about the timing behavior of a model?

1. If the parameters are simple and can stand alone as measurements, then they can be added to designs as a Measure object with appropriate units and type. For example, if you have biological devices with a 90 minute propagation delay, then on the Component representing the device you can add a Measure with numerical value 90, units of om:minute. You'd likely want two types, one of SBO:0000225 (Delay), and a custom type for your own notion of propagation delay, since I don't think that's included in any ontology yet.