diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 4b2b323a3..49a8a2087 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -63,7 +63,7 @@ jobs:
         conda env remove -n "${{ steps.reqs.outputs.envname }}"
   test:
     defaults: {run: {shell: 'bash -el {0}'}}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     strategy:
       matrix:
         include:
@@ -88,7 +88,7 @@ jobs:
     - name: test
       run: python -m unittest discover -v ./Wrappers/Python/test
   conda-matrix:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     outputs:
       python-version: ${{ steps.matrix.outputs.python-version }}
       numpy-version: ${{ steps.matrix.outputs.numpy-version }}
@@ -104,7 +104,7 @@ jobs:
         fi
   conda:
     defaults: {run: {shell: 'bash -el {0}'}}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     needs: conda-matrix
     strategy:
       matrix:
@@ -148,7 +148,7 @@ jobs:
   conda-reindex:
     if: startsWith(github.ref, 'refs/tags')
     needs: conda
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
     - name: conda index tomography.stfc.ac.uk/conda
       run: |
@@ -158,7 +158,7 @@ jobs:
           'bash -lic "conda index --bz2 --zst --run-exports --channeldata --rss -n ccpi ${{ secrets.STFC_SSH_CONDA_DIR }}"'
   docs:
     defaults: {run: {shell: 'bash -el {0}', working-directory: docs}}
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
     - uses: actions/checkout@v4
       with:
@@ -212,7 +212,7 @@ jobs:
         dir: docs/build
         nojekyll: true
   docker:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     permissions:
       contents: read
       packages: write
@@ -264,5 +264,5 @@ jobs:
         labels: ${{ steps.meta.outputs.labels }}
   pass:
     needs: [test-cuda, test, conda, docs, docker]
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps: [{run: echo success}]
diff --git a/.github/workflows/skip.yml b/.github/workflows/skip.yml
index 20282686b..34e046e80 100644
--- a/.github/workflows/skip.yml
+++ b/.github/workflows/skip.yml
@@ -12,5 +12,5 @@ on:
     - 'README.md'
 jobs:
   pass:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps: [{run: echo success}]