diff --git a/test/headers.js b/test/headers.js
index 90c40ef..ef7b705 100644
--- a/test/headers.js
+++ b/test/headers.js
@@ -140,7 +140,7 @@ describe('Headers', () => {
 		res.g = {a: 1};
 		res.h = undefined;
 		res.i = null;
-		res.j = NaN;
+		res.j = Number.NaN;
 		res.k = true;
 		res.l = false;
 		res.m = Buffer.from('test');