diff --git a/.github/workflows/run_tests_each_PR.yml b/.github/workflows/run_tests_each_PR.yml
index dc89cef..e54f7ab 100644
--- a/.github/workflows/run_tests_each_PR.yml
+++ b/.github/workflows/run_tests_each_PR.yml
@@ -3,7 +3,11 @@
 
 name: Run tests each PR
 
-on: push
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
 
 jobs:
   build: