diff --git a/src/libais/ais1_2_3.cpp b/src/libais/ais1_2_3.cpp
index e39e400..3478591 100644
--- a/src/libais/ais1_2_3.cpp
+++ b/src/libais/ais1_2_3.cpp
@@ -4,8 +4,6 @@
 
 #include "ais.h"
 
-using std::abs;
-
 namespace libais {
 
 Ais1_2_3::Ais1_2_3(const char *nmea_payload, const size_t pad)
@@ -35,7 +33,7 @@ Ais1_2_3::Ais1_2_3(const char *nmea_payload, const size_t pad)
   nav_status = bits.ToUnsignedInt(38, 4);
 
   rot_raw = bits.ToInt(42, 8);
-  rot_over_range = abs(rot_raw) > 126 ? true : false;
+  rot_over_range = std::abs(rot_raw) > 126 ? true : false;
   rot = pow((rot_raw/4.733), 2);
   if (rot_raw < 0) rot = -rot;