diff --git a/src/simulator/src/eventQueue.js b/src/simulator/src/eventQueue.ts
similarity index 87%
rename from src/simulator/src/eventQueue.js
rename to src/simulator/src/eventQueue.ts
index a99cbfa9..349f137c 100644
--- a/src/simulator/src/eventQueue.js
+++ b/src/simulator/src/eventQueue.ts
@@ -2,19 +2,29 @@
  * Event Queue is simply a priority Queue, basic implementation O(n^2).
  * @category eventQueue
  */
+
+interface QueueObject {
+    queueProperties: {
+        inQueue: boolean
+        time: number
+        index: number
+    }
+    propagationDelay: number
+}
+
 export class EventQueue {
-    constructor(size) {
+    size: number
+    queue: Array<QueueObject>
+    frontIndex: number
+    time: number
+    constructor(size: number) {
         this.size = size
         this.queue = new Array(size)
         this.frontIndex = 0
         this.time = 0
     }
 
-    /**
-     * @param {CircuitElement} obj - the elemnt to be added
-     * @param {number} delay - the delay in adding an object to queue
-     */
-    add(obj, delay) {
+    add(obj: QueueObject, delay: number) {
         if (obj.queueProperties.inQueue) {
             obj.queueProperties.time =
                 this.time + (delay || obj.propagationDelay)
@@ -59,7 +69,7 @@ export class EventQueue {
      * To add without any delay.
      * @param {CircuitElement} obj - the object to be added
      */
-    addImmediate(obj) {
+    addImmediate(obj: QueueObject) {
         this.queue[this.frontIndex] = obj
         obj.queueProperties.time = this.time
         obj.queueProperties.index = this.frontIndex
@@ -69,10 +79,8 @@ export class EventQueue {
 
     /**
      * Function to swap two objects in queue.
-     * @param {number} v1
-     * @param {number} v2
      */
-    swap(v1, v2) {
+    swap(v1: number, v2: number) {
         const obj1 = this.queue[v1]
         obj1.queueProperties.index = v2