diff --git a/divelist.c b/divelist.c
index eb8f23143..bf853ec0e 100644
--- a/divelist.c
+++ b/divelist.c
@@ -335,6 +335,14 @@ static int calculate_sac(struct dive *dive)
 	return sac * 1000;
 }
 
+void update_cylinder_related_info(struct dive *dive)
+{
+	if(dive != NULL) {
+		dive->sac = calculate_sac(dive);
+		dive->otu = calculate_otu(dive);
+	}
+}
+
 static void get_string(char **str, const char *s)
 {
 	int len;
@@ -452,8 +460,7 @@ static void fill_dive_list(void)
 	for (i = 0; i < dive_table.nr; i++) {
 		struct dive *dive = dive_table.dives[i];
 
-		dive->otu = calculate_otu(dive);
-		dive->sac = calculate_sac(dive);
+		update_cylinder_related_info(dive);
 		gtk_list_store_append(store, &iter);
 		gtk_list_store_set(store, &iter,
 			DIVE_INDEX, i,
diff --git a/divelist.h b/divelist.h
index 2635b7541..c170941db 100644
--- a/divelist.h
+++ b/divelist.h
@@ -7,7 +7,7 @@ extern void dive_list_update_dives(void);
 extern void update_dive_list_col_visibility(void);
 extern void update_dive_list_units(void);
 extern void flush_divelist(struct dive *);
-
+extern void update_cylinder_related_info(struct dive *);
 extern void mark_divelist_changed(int);
 extern int unsaved_changes(void);
 #endif
diff --git a/equipment.c b/equipment.c
index 19abbe672..dbe1f0f13 100644
--- a/equipment.c
+++ b/equipment.c
@@ -416,12 +416,14 @@ static void record_cylinder_changes(cylinder_t *cyl, struct cylinder_widget *cyl
 	desc = gtk_combo_box_get_active_text(box);
 	volume = gtk_spin_button_get_value(cylinder->size);
 	pressure = gtk_spin_button_get_value(cylinder->pressure);
-	start = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->start));
-	end = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->end));
-	if (!gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(cylinder->pressure_button)))
+	if (gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(cylinder->pressure_button))) {
+		start = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->start));
+		end = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->end));
+	} else
 		start = end = 0;
-	o2 = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->o2))*10 + 0.5;
-	if (!gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(cylinder->gasmix_button)))
+	if (gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(cylinder->gasmix_button)))
+		o2 = gtk_spin_button_get_value(GTK_SPIN_BUTTON(cylinder->o2))*10 + 0.5;
+	else
 		o2 = 0;
 	fill_cylinder_info(cylinder, cyl, desc, volume, pressure, start, end, o2);
 }
@@ -643,6 +645,7 @@ static int edit_cylinder_dialog(int index, cylinder_t *cyl)
 		record_cylinder_changes(cyl, &cylinder);
 		dive->cylinder[index] = *cyl;
 		mark_divelist_changed(TRUE);
+		update_cylinder_related_info(dive);
 		flush_divelist(dive);
 	}