diff --git a/Detectors/TOF/calibration/include/TOFCalibration/TOFDiagnosticCalibrator.h b/Detectors/TOF/calibration/include/TOFCalibration/TOFDiagnosticCalibrator.h
index 7b23df6040d3d..fccfcf51fdaa9 100644
--- a/Detectors/TOF/calibration/include/TOFCalibration/TOFDiagnosticCalibrator.h
+++ b/Detectors/TOF/calibration/include/TOFCalibration/TOFDiagnosticCalibrator.h
@@ -31,9 +31,9 @@ class TOFDiagnosticCalibrator final : public o2::calibration::TimeSlotCalibratio
   int mRunNumber = -1;
 
  public:
-  TOFDiagnosticCalibrator() = default;
+  TOFDiagnosticCalibrator(int minROwin = 100) : mMinROwin(minROwin) {}
   ~TOFDiagnosticCalibrator() final = default;
-  bool hasEnoughData(const Slot& slot) const final { return true; }
+  bool hasEnoughData(const Slot& slot) const final;
   void initOutput() final;
   void finalizeSlot(Slot& slot) final;
   Slot& emplaceNewSlot(bool front, TFType tstart, TFType tend) final;
@@ -43,12 +43,15 @@ class TOFDiagnosticCalibrator final : public o2::calibration::TimeSlotCalibratio
   const std::vector<Diagnostic>& getDiagnosticVector() const { return mDiagnosticVector; }
   const CcdbObjectInfoVector& getDiagnosticInfoVector() const { return mccdbInfoVector; }
   CcdbObjectInfoVector& getDiagnosticInfoVector() { return mccdbInfoVector; }
+  int getMinROwin() const { return mMinROwin; }
+  void setMinROwin(int rowin) { mMinROwin = rowin; }
 
  private:
   CcdbObjectInfoVector mccdbInfoVector;
   std::vector<Diagnostic> mDiagnosticVector;
+  int mMinROwin; // minimal number of readout windows needed to finalize the object
 
-  ClassDefOverride(TOFDiagnosticCalibrator, 1);
+  ClassDefOverride(TOFDiagnosticCalibrator, 2);
 };
 
 } // end namespace tof
diff --git a/Detectors/TOF/calibration/src/TOFDiagnosticCalibrator.cxx b/Detectors/TOF/calibration/src/TOFDiagnosticCalibrator.cxx
index 9a4118dbba493..f238d69bb75ed 100644
--- a/Detectors/TOF/calibration/src/TOFDiagnosticCalibrator.cxx
+++ b/Detectors/TOF/calibration/src/TOFDiagnosticCalibrator.cxx
@@ -28,7 +28,17 @@ void TOFDiagnosticCalibrator::initOutput()
   mccdbInfoVector.clear();
   mDiagnosticVector.clear();
 }
+//----------------------------------------------------------
+bool TOFDiagnosticCalibrator::hasEnoughData(const Slot& slot) const
+{
+  const Diagnostic* diag = slot.getContainer();
 
+  if (diag->getFrequencyROW() < mMinROwin) {
+    return false;
+  }
+
+  return true;
+}
 //----------------------------------------------------------
 void TOFDiagnosticCalibrator::finalizeSlot(Slot& slot)
 {
diff --git a/Detectors/TOF/calibration/testWorkflow/TOFDiagnosticCalibratorSpec.h b/Detectors/TOF/calibration/testWorkflow/TOFDiagnosticCalibratorSpec.h
index 7887ff848d544..91b931f3b96b3 100644
--- a/Detectors/TOF/calibration/testWorkflow/TOFDiagnosticCalibratorSpec.h
+++ b/Detectors/TOF/calibration/testWorkflow/TOFDiagnosticCalibratorSpec.h
@@ -37,7 +37,7 @@ namespace calibration
 class TOFDiagnosticCalibDevice : public o2::framework::Task
 {
  public:
-  TOFDiagnosticCalibDevice(std::shared_ptr<o2::base::GRPGeomRequest> req, int runnumber = -1) : mCCDBRequest(req), mRunNumber(runnumber) {}
+  TOFDiagnosticCalibDevice(std::shared_ptr<o2::base::GRPGeomRequest> req, int runnumber = -1, int rowinMin = 100000) : mCCDBRequest(req), mRunNumber(runnumber), mMinROwin(rowinMin) {}
   void init(o2::framework::InitContext& ic) final
   {
     o2::base::GRPGeomHelper::instance().setRequest(mCCDBRequest);
@@ -47,6 +47,7 @@ class TOFDiagnosticCalibDevice : public o2::framework::Task
     mCalibrator->setSlotLength(slotL);
     mCalibrator->setMaxSlotsDelay(delay);
     mCalibrator->setRunNumber(mRunNumber);
+    mCalibrator->setMinROwin(mMinROwin);
   }
 
   void finaliseCCDB(o2::framework::ConcreteDataMatcher& matcher, void* obj) final
@@ -75,6 +76,7 @@ class TOFDiagnosticCalibDevice : public o2::framework::Task
   std::unique_ptr<o2::tof::TOFDiagnosticCalibrator> mCalibrator;
   std::shared_ptr<o2::base::GRPGeomRequest> mCCDBRequest;
   int mRunNumber = -1;
+  int mMinROwin = 100000;
 
   //________________________________________________________________
   void sendOutput(DataAllocator& output)
@@ -104,7 +106,7 @@ class TOFDiagnosticCalibDevice : public o2::framework::Task
 namespace framework
 {
 
-DataProcessorSpec getTOFDiagnosticCalibDeviceSpec(int runnumber)
+DataProcessorSpec getTOFDiagnosticCalibDeviceSpec(int runnumber, int rowinMin)
 {
   using device = o2::calibration::TOFDiagnosticCalibDevice;
   using clbUtils = o2::calibration::Utils;
@@ -125,7 +127,7 @@ DataProcessorSpec getTOFDiagnosticCalibDeviceSpec(int runnumber)
     "tof-diagnostic-calibration",
     inputs,
     outputs,
-    AlgorithmSpec{adaptFromTask<device>(ccdbRequest, runnumber)},
+    AlgorithmSpec{adaptFromTask<device>(ccdbRequest, runnumber, rowinMin)},
     Options{
       {"tf-per-slot", VariantType::UInt32, 5u, {"number of TFs per calibration time slot"}},
       {"max-delay", VariantType::UInt32, 3u, {"number of slots in past to consider"}}}};
diff --git a/Detectors/TOF/calibration/testWorkflow/tof-diagnostic-workflow.cxx b/Detectors/TOF/calibration/testWorkflow/tof-diagnostic-workflow.cxx
index 3cde7be96867a..b45fcc2b5498c 100644
--- a/Detectors/TOF/calibration/testWorkflow/tof-diagnostic-workflow.cxx
+++ b/Detectors/TOF/calibration/testWorkflow/tof-diagnostic-workflow.cxx
@@ -19,6 +19,7 @@ void customize(std::vector<o2::framework::ConfigParamSpec>& workflowOptions)
 {
   // option allowing to set parameters
   workflowOptions.push_back(ConfigParamSpec{"tof-dia-run-number", o2::framework::VariantType::Int, -1, {"run number"}});
+  workflowOptions.push_back(ConfigParamSpec{"tof-dia-min-rowin", o2::framework::VariantType::Int, 100000, {"min number of TOF Readout Windows, def=100k (3 s)"}});
 }
 
 // ------------------------------------------------------------------
@@ -29,6 +30,7 @@ WorkflowSpec defineDataProcessing(ConfigContext const& configcontext)
 {
   WorkflowSpec specs;
   auto runnumber = configcontext.options().get<int>("tof-dia-run-number");
-  specs.emplace_back(getTOFDiagnosticCalibDeviceSpec(runnumber));
+  auto rowinMin = configcontext.options().get<int>("tof-dia-min-rowin");
+  specs.emplace_back(getTOFDiagnosticCalibDeviceSpec(runnumber, rowinMin));
   return specs;
 }