diff --git a/js/common/model/Scene.js b/js/common/model/Scene.js
index 7866f828..fbc81137 100644
--- a/js/common/model/Scene.js
+++ b/js/common/model/Scene.js
@@ -348,7 +348,7 @@ define( require => {
           const angularFrequency = Math.PI * 2 * frequency;
 
           // For 50% longer than one pulse, keep the oscillator fixed at 0 to prevent "ringing"
-          let waveValue = ( this.pulseFiringProperty.get() && timeSincePulseStarted > period ) ? 0 :
+          const waveValue = ( this.pulseFiringProperty.get() && timeSincePulseStarted > period ) ? 0 :
                           -Math.sin( time * angularFrequency + this.phase ) * amplitude;
 
           // assumes a square lattice
diff --git a/js/common/view/LightEmitterNode.js b/js/common/view/LightEmitterNode.js
index 6675f59f..90937447 100644
--- a/js/common/view/LightEmitterNode.js
+++ b/js/common/view/LightEmitterNode.js
@@ -30,7 +30,7 @@ define( require => {
      * @param {boolean} isPrimarySource
      */
     constructor( model, waveAreaNode, isPrimarySource ) {
-      let scene = model.lightScene;
+      const scene = model.lightScene;
       const laserPointerNode = new LaserPointerNode( scene.button1PressedProperty, _.extend( {
         rightCenter: waveAreaNode.leftCenter.plusXY( 20, 0 )
       }, DEFAULT_OPTIONS ) );
diff --git a/js/common/view/WaveInterferenceControlPanel.js b/js/common/view/WaveInterferenceControlPanel.js
index 10d65c3c..ba8726f8 100644
--- a/js/common/view/WaveInterferenceControlPanel.js
+++ b/js/common/view/WaveInterferenceControlPanel.js
@@ -186,7 +186,7 @@ define( require => {
       if ( options.additionalControl ) {options.additionalControl.centerX = centerX;}
       sceneRadioButtons.centerX = centerX;
       separator.centerX = centerX;
-      let minX = _.min( [
+      const minX = _.min( [
         frequencySliderContainer.left,
         amplitudeSliderContainer.left,
         frequencyTitle.left,
diff --git a/js/common/view/WaveMeterNode.js b/js/common/view/WaveMeterNode.js
index 4684ba07..b93b7b3c 100644
--- a/js/common/view/WaveMeterNode.js
+++ b/js/common/view/WaveMeterNode.js
@@ -146,7 +146,7 @@ define( require => {
           // Set the range by incorporating the model's time units, so it will match with the timer.
           const maxSeconds = NUMBER_OF_TIME_DIVISIONS;
 
-          let scene = model.sceneProperty.value;
+          const scene = model.sceneProperty.value;
           if ( model.isWaveMeterInPlayAreaProperty.get() ) {
 
             // Look up the location of the cell. The probe node has the cross-hairs at 0,0, so we can use the