Signal events can be handy in many process scenarios to steer the process flow. In the BPMN standard, Start, End and Intermediate Events can be of the type Signal. 

Note! Barium Live currently only support catching and throwing intermediate signal events as well as catching interrupting boundary events that exist within the same pool and at the same process level. 

If you need to reach another process you can use a Subprocess or a call activity.   

How to use Intermediate Signal Events

Throwing Intermediate Signal Event is used to send signals. The event is configured with a Signal Name that will be thrown when the event is triggered. One or several Catching Signal Events can listen for the signal.

Catching Intermediate Signal Event is used to receive signals.  The event is configured with a Signal Name to listen for and when such signal occurs, the event will be triggered. 

Catching Intermediate Signal Events can also be used as interrupting boundary event.  

Configure a signal event

1. Open the settings panel by double-click the Intermediate event.

2. Choose Event trigger to be either a throwing or catching Signal.

3. Specify the name of the Signal that you want to send (throw) or listen for (catch)

Above: Throwing Intermediate Signal Event configured

to send the signal CANCEL.

When to use Intermediate Signal Events


Signal Events can be useful in many scenarios, one example is when you want to synchronize activities in complex processes. Another one is for interruption, for example if you want to stop one or several participant to perform tasks due to something happening in the process that requires the process flow to change significantly. In the below example, if Task A is completed before Task C then Task C will be cancelled and the lower process flow will thus never reach Task D.