diff --git a/src/gui/browser.js b/src/gui/browser.js
index 23350fd981..b349683ba2 100644
--- a/src/gui/browser.js
+++ b/src/gui/browser.js
@@ -38,24 +38,32 @@ dwv.browser.hasTypedArray = function()
     return "Uint8Array" in window && "Uint16Array" in window;
 };
 
+//only check at startup (since we propose a replacement)
+dwv.browser._hasTypedArraySlice = (typeof Uint8Array.prototype.slice !== "undefined");
+
 /**
  * Browser check for typed array slice method.
  * Missing in Internet Explorer 11.
  */
 dwv.browser.hasTypedArraySlice = function()
 {
-    return (typeof Uint8Array.prototype.slice !== "undefined");
+    return dwv.browser._hasTypedArraySlice;
 };
 
+// only check at startup (since we propose a replacement)
+dwv.browser._hasFloat64Array = ("Float64Array" in window);
+
 /**
  * Browser check for Float64Array array.
  * Missing in PhantomJS 1.9.20 (on Travis).
  */
 dwv.browser.hasFloat64Array = function()
 {
-    return "Float64Array" in window;
+    return dwv.browser._hasFloat64Array;
 };
 
+//only check at startup (since we propose a replacement)
+dwv.browser._hasClampedArray = ("Uint8ClampedArray" in window);
 
 /**
  * Browser check for clamped array.
@@ -65,7 +73,7 @@ dwv.browser.hasFloat64Array = function()
  */
 dwv.browser.hasClampedArray = function()
 {
-    return "Uint8ClampedArray" in window;
+    return dwv.browser._hasClampedArray;
 };
 
 /**
@@ -126,4 +134,12 @@ dwv.browser.check = function()
         // TODO Find better replacement!
         window.Uint8ClampedArray = window.Uint8Array;
     }
+    // check Float64 array
+    if( !dwv.browser.hasFloat64Array() ) {
+        // silent fail with warning
+        console.warn("The Float64Array is not supported in this browser. This may impair performance. ");
+        // Use Float32Array instead... Not good
+        // TODO Find better replacement!
+        window.Float64Array = window.Float32Array;
+    }
 };
diff --git a/tests/image/view.test.js b/tests/image/view.test.js
index d10f1bc836..cb877b7bf8 100644
--- a/tests/image/view.test.js
+++ b/tests/image/view.test.js
@@ -64,8 +64,7 @@ QUnit.test("Test generate data MONO.", function (assert) {
     // create a view
     var view0 = new dwv.image.View(image0);
     // create the image data
-    // TODO Uint8ClampedArray not in phantom??
-    var imageData = {'width': size0, 'height': size0, 'data': new Uint8Array(size0*size0*4) };
+    var imageData = {'width': size0, 'height': size0, 'data': new Uint8ClampedArray(size0*size0*4) };
 
     // default window level
     view0.setWindowLevelMinMax();
@@ -112,8 +111,7 @@ QUnit.test("Test generate data RGB.", function (assert) {
     // create a view
     var view0 = new dwv.image.View(image0);
     // create the image data
-    // TODO Uint8ClampedArray not in phantom??
-    var imageData = {'width': size0, 'height': size0, 'data': new Uint8Array(size0*size0*4) };
+    var imageData = {'width': size0, 'height': size0, 'data': new Uint8ClampedArray(size0*size0*4) };
 
     // default window level
     view0.setWindowLevel(127, 255);