diff --git a/CHANGELOG.md b/CHANGELOG.md
index e68cf15..5743240 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## [v3.4.6]
+
+* Fixed incorrect imperial unit display of 'mill' to 'mil' in the IPC2151 track current calculator.
+* Plane proximity input value is disabled if "is plane present" select is set to False in the IPC2151 track current calculator.
+
 ## [v3.4.5](https://github.com/gbmhunter/NinjaCalc/tree/v3.4.5) (2023-02-19)
 
 ### Features
diff --git a/components/calc-var-input.js b/components/calc-var-input.js
index be2426b..16cf442 100644
--- a/components/calc-var-input.js
+++ b/components/calc-var-input.js
@@ -32,6 +32,9 @@ export class CalcVarInput extends React.Component {
       throw Error('Direction of "' + calcVar.direction + '" not supported.')
     }
 
+    if (this.props.disabled) {
+      disabled = true
+    }
 
     const validationState = calcVar.validation.state
 
diff --git a/components/calc-var-row.js b/components/calc-var-row.js
index 1566439..200979d 100644
--- a/components/calc-var-row.js
+++ b/components/calc-var-row.js
@@ -59,7 +59,8 @@ class VarRow extends React.Component {
                     id={this.props.id}
                     calc={this.props.calc}
                     valueChanged={this.props.valueChanged}
-                    width={this.props.width} />
+                    width={this.props.width}
+                    disabled={disabled} />
     } else if (calcVar.type === 'select') {
       const options = calcVar.options.map((option, idx) => {
         return (
diff --git a/pages/calculators/electronics/pcb-design/track-current-ipc2152/index.js b/pages/calculators/electronics/pcb-design/track-current-ipc2152/index.js
index 0c21a17..690320a 100644
--- a/pages/calculators/electronics/pcb-design/track-current-ipc2152/index.js
+++ b/pages/calculators/electronics/pcb-design/track-current-ipc2152/index.js
@@ -186,7 +186,7 @@ class UI extends React.Component {
             dispVal: "35",
             units: [
               new UnitsMultiplicative('um', 1e-6),
-              new UnitsMultiplicative('mill', unitConversionConstants.METERS_PER_MILS),
+              new UnitsMultiplicative('mil', unitConversionConstants.METERS_PER_MILS),
               new UnitsMultiplicative('oz', unitConversionConstants.COPPER_THICKNESS_M_PER_OZ),
             ],
             selUnit: "um",
@@ -195,18 +195,18 @@ class UI extends React.Component {
                 if (value < 17.5e-6)
                   return [
                     "warning",
-                    "Track thickness is below the minimum value (17.5um) extracted from the track thickness modififer graph in IPC-2152. Results might not be as accurate (extrapolation will occur).",
+                    "Track thickness is below the minimum value (17.5um/0.5oz) extracted from the track thickness modifier graph in IPC-2152. Results might not be as accurate (extrapolation will occur).",
                   ];
                 if (value > 105.0036e-6)
                   return [
                     "warning",
-                    "Track thickness is above the maximum value (105um) extracted from the track thickness modififer graph in IPC-2152. Results might not be as accurate (extrapolation will occur).",
+                    "Track thickness is above the maximum value (105um) extracted from the track thickness modifier graph in IPC-2152. Results might not be as accurate (extrapolation will occur).",
                   ];
                 return ["ok", ""];
               },
             },
             helpText:
-              "The thickness (height) of the track. This is equal to the thickness of the copper layer the track is on. This is also called the copper weight. Common values are 17um (0.5oz) or 35um (1oz).",
+              "The thickness (height) of the track. This is equal to the thickness of the copper layer the track is on. This is also called the copper weight. Common values are 17.5um (0.5oz) or 35um (1oz).",
           }), // trackThickness
 
           trackThicknessModifier: new CalcVar({
@@ -229,7 +229,7 @@ class UI extends React.Component {
             dispVal: "1.6",
             units: [
               new UnitsMultiplicative('mm', 1e-3),
-              new UnitsMultiplicative('mill', unitConversionConstants.METERS_PER_MILS),
+              new UnitsMultiplicative('mil', unitConversionConstants.METERS_PER_MILS),
             ],
             selUnit: "mm",
             validation: {
@@ -277,7 +277,7 @@ class UI extends React.Component {
             options: ["Yes", "No"],
             selOption: "Yes",
             helpText:
-              'Set this to "True" if there is a copper plane either above or below the current-carrying track, and then enter the distance to it in the "Plane Proximity" field. If there is no plane, set this to "False", and the "Plane Proximity" variable will also disappear.',
+              'Set this to "True" if there is a copper plane either above or below the current-carrying track, and then enter the distance to it in the "Plane Proximity" field. If there is no plane, set this to "False", and the "Plane Proximity" variable will be disabled.',
           }),
 
           // ============================================================================================= //
@@ -290,7 +290,7 @@ class UI extends React.Component {
             dispVal: "1.6",
             units: [              
               new UnitsMultiplicative('mm', 1e-3),
-              new UnitsMultiplicative('mill', unitConversionConstants.METERS_PER_MILS),
+              new UnitsMultiplicative('mil', unitConversionConstants.METERS_PER_MILS),
             ],
             selUnit: "mm",
             validation: {
@@ -404,7 +404,7 @@ class UI extends React.Component {
             direction: "output",
             units: [
               new UnitsMultiplicative('mm', 1e-3),
-              new UnitsMultiplicative('mill', unitConversionConstants.METERS_PER_MILS),
+              new UnitsMultiplicative('mil', unitConversionConstants.METERS_PER_MILS),
             ],
             selUnit: "mm",
             sigFig: 3,