diff --git a/.travis.yml b/.travis.yml
index 76dd5d7dc4d3..00d4a740b662 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -27,7 +27,7 @@ install:
 before_script:
   - gem install travis-artifacts
   - export DISPLAY=:99.0
-  - export LIGHTHOUSE_CHROMIUM_PATH="$(pwd)/chrome-linux/chrome"
+  - export CHROME_PATH="$(pwd)/chrome-linux/chrome"
   - sh -e /etc/init.d/xvfb start
   - sleep 3 # wait for xvfb to boot
   - yarn build-all
diff --git a/chrome-launcher/chrome-finder.ts b/chrome-launcher/chrome-finder.ts
index d4bda1b16730..6504b5fa57f8 100644
--- a/chrome-launcher/chrome-finder.ts
+++ b/chrome-launcher/chrome-finder.ts
@@ -53,11 +53,17 @@ export function darwin() {
     {regex: /^\/Applications\/.*Chrome Canary.app/, weight: 101},
     {regex: /^\/Volumes\/.*Chrome.app/, weight: -2},
     {regex: /^\/Volumes\/.*Chrome Canary.app/, weight: -1},
-    {regex: new RegExp(process.env.LIGHTHOUSE_CHROMIUM_PATH), weight: 150},
-    {regex: new RegExp(process.env.CHROME_PATH), weight: 151}
   ];
-  // clang-format on
 
+  if (process.env.LIGHTHOUSE_CHROMIUM_PATH) {
+    priorities.push({regex: new RegExp(process.env.LIGHTHOUSE_CHROMIUM_PATH), weight: 150});
+  }
+
+  if (process.env.CHROME_PATH) {
+    priorities.push({regex: new RegExp(process.env.CHROME_PATH), weight: 151});
+  }
+
+  // clang-format on
   return sort(installations, priorities);
 }
 
@@ -107,8 +113,7 @@ export function linux() {
   ];
   executables.forEach((executable: string) => {
     try {
-      const chromePath =
-          execFileSync('which', [executable]).toString().split(newLineRegex)[0];
+      const chromePath = execFileSync('which', [executable]).toString().split(newLineRegex)[0];
 
       if (canAccess(chromePath)) {
         installations.push(chromePath);
@@ -125,12 +130,19 @@ export function linux() {
   }
 
   const priorities: Priorities = [
-    {regex: /chrome-wrapper$/, weight: 51}, {regex: /google-chrome-stable$/, weight: 50},
+    {regex: /chrome-wrapper$/, weight: 51},
+    {regex: /google-chrome-stable$/, weight: 50},
     {regex: /google-chrome$/, weight: 49},
-    {regex: new RegExp(process.env.LIGHTHOUSE_CHROMIUM_PATH), weight: 100},
-    {regex: new RegExp(process.env.CHROME_PATH), weight: 101}
   ];
 
+  if (process.env.LIGHTHOUSE_CHROMIUM_PATH) {
+    priorities.push({regex: new RegExp(process.env.LIGHTHOUSE_CHROMIUM_PATH), weight: 100});
+  }
+
+  if (process.env.CHROME_PATH) {
+    priorities.push({regex: new RegExp(process.env.CHROME_PATH), weight: 101});
+  }
+
   return sort(uniq(installations.filter(Boolean)), priorities);
 }