diff --git a/src/obidmscolumn.c b/src/obidmscolumn.c
index 76939da..d55338b 100644
--- a/src/obidmscolumn.c
+++ b/src/obidmscolumn.c
@@ -907,8 +907,9 @@ OBIDMS_column_p obi_open_column(OBIDMS_p dms,
 	// TODO Check endianness?
 
 	// Compute data size from the informations in the header
-	data_size = ((column->header)->line_count) * sizeof((column->header)->data_type);
+	data_size = obi_array_sizeof((column->header)->data_type, (column->header)->line_count, (column->header)->nb_elements_per_line);
 
+	// Map the data
 	column->data   			 = mmap(NULL,
 			                 	 	data_size,
 			                 	 	PROT_READ,
@@ -1009,7 +1010,7 @@ int obi_close_column(OBIDMS_column_p column)
 	size_t data_size;
 
 	// Munmap data
-	data_size = (column->header)->line_count * (column->header)->nb_elements_per_line * sizeof((column->header)->data_type);
+	data_size = obi_array_sizeof((column->header)->data_type, (column->header)->line_count, (column->header)->nb_elements_per_line);
 	if (munmap(column->data, data_size) < 0)
 	{
 		obi_set_errno(OBICOL_UNKNOWN_ERROR);
@@ -1025,6 +1026,8 @@ int obi_close_column(OBIDMS_column_p column)
 		return -1;
 	}
 
+	obi_close_column_directory(column->column_directory);
+
 	free(column);
 
 	return 0;