diff --git a/anonymizer_core_refactored_onnx.py b/anonymizer_core_refactored_onnx.py
index 1b851b8..171c7c1 100644
--- a/anonymizer_core_refactored_onnx.py
+++ b/anonymizer_core_refactored_onnx.py
@@ -4279,6 +4279,30 @@ def process_pdf(
     cfg = load_dictionaries(config_path)
     pages_text, tables_lines, ocr_used, ocr_word_map = extract_text_with_fallback_ocr(pdf_path)
 
+    # Q-1 B-3 : pré-flight texte vide. Si moins de SEUIL_TEXTE_MINI caractères
+    # extraits, c'est probablement un scan non-OCRisé ou un document corrompu.
+    # On NE traite PAS — quarantaine totale, le doc original est copié pour
+    # ré-essai manuel.
+    extracted_chars = sum(len(p) for p in pages_text)
+    if extracted_chars < SEUIL_TEXTE_MINI:
+        log.warning("Preflight failed for %s: only %d chars extracted (seuil=%d)",
+                    pdf_path.name, extracted_chars, SEUIL_TEXTE_MINI)
+        if quarantine_mgr is not None:
+            quarantine_mgr.flag(
+                doc_name=pdf_path.stem,
+                reason="preflight_text_too_short",
+                detail=f"Only {extracted_chars} chars extracted from {len(pages_text)} pages (seuil={SEUIL_TEXTE_MINI})",
+                severity="full",
+                extracted_chars=extracted_chars,
+            )
+            try:
+                quarantine_mgr.quarantine_dir.mkdir(parents=True, exist_ok=True)
+                shutil.copy(pdf_path, quarantine_mgr.quarantine_dir / pdf_path.name)
+            except Exception as copy_err:
+                log.warning("Could not copy original PDF to quarantine for %s: %s",
+                            pdf_path.name, copy_err)
+        return {}
+
     # 1) Regex rules + NER-first cross-validation
     # Passer les NER managers pour que anonymise_document_regex exécute le NER
     # sur le texte original (non masqué) et valide les noms extraits par regex