diff --git a/.github/workflows/deploy-dtds.yaml b/.github/workflows/deploy-dtds.yaml
index bb48f61d27b..caf62f55141 100644
--- a/.github/workflows/deploy-dtds.yaml
+++ b/.github/workflows/deploy-dtds.yaml
@@ -1,14 +1,15 @@
 name: deploy-dtds-on-website
 
 on:
-  push:
-    branches:
-      - master
+  pull_request:
+    types:
+      - closed
     paths:
-      - matsim/src/main/resources/dtd
+      - 'matsim/src/main/resources/dtd/**'
 
 jobs:
   rsync-dtds:
+    if: github.event.pull_request.merged == true  // only if PR closed by merging
     name: sync DTDs to website
     runs-on: ubuntu-latest