diff --git a/inst/lat/src/GLATAeff.cpp b/inst/lat/src/GLATAeff.cpp
index 7c9e871..6e5249d 100644
--- a/inst/lat/src/GLATAeff.cpp
+++ b/inst/lat/src/GLATAeff.cpp
@@ -164,6 +164,11 @@ double GLATAeff::operator() (const double& logE, const double& ctheta)
     double aeff = (ctheta >= m_min_ctheta) 
                   ? m_aeff_bins.interpolate(logE, ctheta, m_aeff) : 0.0;
 
+    // Make sure that effective area is not negative
+    if (aeff < 0.0) {
+        aeff = 0.0;
+    }
+    
     // Return effective area value
     return aeff;
 }
@@ -185,6 +190,11 @@ double GLATAeff::operator() (const double& logE, const double& ctheta,
     double aeff = (ctheta >= m_min_ctheta) 
                   ? m_aeff_bins.interpolate(logE, ctheta, m_aeff) : 0.0;
 
+    // Make sure that effective area is not negative
+    if (aeff < 0.0) {
+        aeff = 0.0;
+    }
+
     // Return effective area value
     return aeff;
 }