- dive->cylinder[i].gasmix.o2.permille = gasmix.oxygen * 1000 + 0.5;
- dive->cylinder[i].gasmix.he.permille = gasmix.helium * 1000 + 0.5;
+ o2 = gasmix.oxygen * 1000 + 0.5;
+ he = gasmix.helium * 1000 + 0.5;
+
+ /* Ignore bogus data - libdivecomputer does some crazy stuff */
+ if (o2 < 210 || o2 >= 1000)
+ o2 = 0;
+ if (he < 0 || he >= 800 || o2+he >= 1000)
+ he = 0;
+
+ dive->cylinder[i].gasmix.o2.permille = o2;
+ dive->cylinder[i].gasmix.he.permille = he;