diff --git a/include/sexpp/sexp.h b/include/sexpp/sexp.h
index 1556f1a..05b6f86 100644
--- a/include/sexpp/sexp.h
+++ b/include/sexpp/sexp.h
@@ -44,6 +44,7 @@
 #include "sexp-public.h"
 #include "sexp-error.h"
 
+namespace std {
 using octet_t = uint8_t;
 
   template<>
@@ -111,7 +112,7 @@ using octet_t = uint8_t;
       not_eof(const int_type& __c) noexcept
       { return (__c == eof()) ? 0 : __c; }
   };
-
+}
 
 
 namespace sexp {