The ariaBusy property of the Element interface reflects the value of the aria-busy attribute, which indicates whether an element is being modified, as assistive technologies may want to wait until the modifications are complete before exposing them to the user.
 
A string with one of the following values:
  "true"  -  
The element is being updated.
   "false"  -  
There are no expected updates for the element.
   
 
In this example the aria-busy attribute on the element with an ID of clock is set to "false". Using ariaBusy we update the value to "true".
 
<div
  id="clock"
  role="timer"
  aria-live="polite"
  aria-atomic="true"
  aria-busy="false"></div>
  
let el = document.getElementById("clock");
console.log(el.ariaBusy); 
el.ariaBusy = "true";
console.log(el.ariaBusy);