diff --git a/field-logic/src/lib/engine.test.ts b/field-logic/src/lib/engine.test.ts
index dcf3bb6..7cc805a 100644
--- a/field-logic/src/lib/engine.test.ts
+++ b/field-logic/src/lib/engine.test.ts
@@ -95,4 +95,8 @@ describe('SurveyEngine', () => {
         expect(session.visitedNodes).toContain('q1');
         expect(session.visitedNodes).toContain('q2_yes');
     });
+
+    it('should throw an error if submitting answer before starting survey', () => {
+        expect(() => engine.submitAnswer('test')).toThrow('Survey not active');
+    });
 });