The firing keyword determines whether all the rules are executed.
This keyword is used to determine whether all the rules of a rule task are executed or only one of them.
Rule task definitions
ruletask ruleTaskName
{
[firing = allrules|rule;]
};
The value following the firing keyword indicates whether all rules are executed (allrules, the default) or whether only one rule is executed (rule).
All instances of one rule are executed. If only one rule is executed, use the keyword firinglimit. See also ruletask for more information.