diff --git a/brjs-sdk/sdk/libs/javascript/br-util/src/br/util/Observable.js b/brjs-sdk/sdk/libs/javascript/br-util/src/br/util/Observable.js
index a3ce0b2f4..259a70f7e 100644
--- a/brjs-sdk/sdk/libs/javascript/br-util/src/br/util/Observable.js
+++ b/brjs-sdk/sdk/libs/javascript/br-util/src/br/util/Observable.js
@@ -1,10 +1,10 @@
-'use strict';
+"use strict";
 
 /**
  * @module br/util/Observable
  */
 
-var Errors = require('br/Errors');
+var Errors = require("br/Errors");
 
 /**
  * Constructs a new <code>Observable</code>.
@@ -66,13 +66,16 @@ Observable.prototype.getCount = function() {
  *  <code>String</code>, <code>Number</code>, <code>Boolean</code> or <code>Function</code>.
  */
 Observable.prototype.addObserver = function(observer) {
-	if (!(observer instanceof Object) ||
-		(observer instanceof String ||
-		observer instanceof Number ||
-		observer instanceof Boolean ||
-		observer instanceof Function)) {
-
-		throw new Errors.InvalidParametersError('An observer must be an object');
+	if (
+		!(typeof observer === "object" && observer !== null) ||
+		(typeof observer === "string" ||
+			(typeof observer === "number" && !isNan(observer)) ||
+			typeof observer === "boolean" ||
+			typeof observer === "function")
+	) {
+		throw new Errors.InvalidParametersError(
+			"An observer must be an object"
+		);
 	}
 
 	this.m_pObservers.push(observer);
@@ -90,7 +93,7 @@ Observable.prototype.addObserver = function(observer) {
  *  <code>String</code>, <code>Number</code>, <code>Boolean</code> or <code>Function</code>.
  */
 Observable.prototype.addUniqueObserver = function(observer) {
-	var observerNotAdded = (this._getObserverIndex(observer) == -1);
+	var observerNotAdded = this._getObserverIndex(observer) == -1;
 
 	if (observerNotAdded) {
 		this.addObserver(observer);
@@ -147,7 +150,7 @@ Observable.prototype.removeAllObservers = function() {
 	this.m_pObservers = [];
 };
 
- /**
+/**
  * Gets a list of all the observers that have been registered with this <code>Observable</code>.
  *
  * @return {Array} A list of the observers that have been registered.
@@ -177,8 +180,10 @@ Observable.prototype.notifyObservers = function(methodName, parameters) {
 	var observersCopy = this.m_pObservers.slice();
 	for (var idx = 0, len = observersCopy.length; idx < len; idx++) {
 		var observer = observersCopy[idx];
-		if (typeof observer[methodName] !== 'function') {
-			throw new Errors.NotSupportedError("Observer does not implement '" + methodName + "'");
+		if (typeof observer[methodName] !== "function") {
+			throw new Errors.NotSupportedError(
+				"Observer does not implement '" + methodName + "'"
+			);
 		}
 
 		observer[methodName].apply(observer, parameters);
@@ -215,7 +220,11 @@ Observable.prototype.notify = function(methodName) {
  *
  * @see br.util.Observable#notifyObservers to notify without guarding against exceptions.
  */
-Observable.prototype.notifyObserversWithTryCatch = function(methodName, parameters, throwExceptions) {
+Observable.prototype.notifyObserversWithTryCatch = function(
+	methodName,
+	parameters,
+	throwExceptions
+) {
 	if (!parameters) {
 		parameters = [];
 	}
@@ -227,7 +236,9 @@ Observable.prototype.notifyObserversWithTryCatch = function(methodName, paramete
 		try {
 			observer[methodName].apply(observer, parameters);
 		} catch (e) {
-			failedNotifications.push(new Observable.FailedNotification(observer, methodName, e));
+			failedNotifications.push(
+				new Observable.FailedNotification(observer, methodName, e)
+			);
 		}
 	}
 
diff --git a/brjs-sdk/sdk/libs/javascript/br-util/test-unit/tests/br/util/ObservableTest.js b/brjs-sdk/sdk/libs/javascript/br-util/test-unit/tests/br/util/ObservableTest.js
index d9f19cf44..a798ffa1e 100644
--- a/brjs-sdk/sdk/libs/javascript/br-util/test-unit/tests/br/util/ObservableTest.js
+++ b/brjs-sdk/sdk/libs/javascript/br-util/test-unit/tests/br/util/ObservableTest.js
@@ -139,11 +139,7 @@
 		assertException(function() { oThis.m_oObservable.addObserver(10); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addNumericObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addObserver(new Number(10)); }, "InvalidParametersError");
-	};
+
 
 	ObservableTest.prototype.test_addStringObserverFails = function()
 	{
@@ -151,11 +147,7 @@
 		assertException(function() { oThis.m_oObservable.addObserver("test"); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addNewStringObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addObserver(new String("test")); }, "InvalidParametersError");
-	};
+
 
 	ObservableTest.prototype.test_addFunctionObserverFails = function()
 	{
@@ -170,11 +162,7 @@
 		assertException(function() { oThis.m_oObservable.addObserver(false); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addBooleanObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addObserver(new Boolean(false)); }, "InvalidParametersError");
-	};
+
 
 	ObservableTest.prototype.test_addDuplicateObserverSucceeds = function()
 	{
@@ -213,24 +201,12 @@
 		assertException(function() { oThis.m_oObservable.addUniqueObserver(10); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addNumericUniqueObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addUniqueObserver(new Number(10)); }, "InvalidParametersError");
-	};
-
 	ObservableTest.prototype.test_addStringUniqueObserverFails = function()
 	{
 		var oThis = this;
 		assertException(function() { oThis.m_oObservable.addUniqueObserver("test"); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addNewStringUniqueObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addUniqueObserver(new String("test")); }, "InvalidParametersError");
-	};
-
 	ObservableTest.prototype.test_addFunctionUniqueObserverFails = function()
 	{
 		var oThis = this;
@@ -244,12 +220,6 @@
 		assertException(function() { oThis.m_oObservable.addUniqueObserver(false); }, "InvalidParametersError");
 	};
 
-	ObservableTest.prototype.test_addBooleanUniqueObserverFails = function()
-	{
-		var oThis = this;
-		assertException(function() { oThis.m_oObservable.addUniqueObserver(new Boolean(false)); }, "InvalidParametersError");
-	};
-
 	ObservableTest.prototype.test_addDuplicateUniqueObserverFails = function()
 	{
 		this.m_oObserver1.expects(once()).method1();