diff --git a/src/elements/gel.c b/src/elements/gel.c
index 2a3f89faf..b805dd673 100644
--- a/src/elements/gel.c
+++ b/src/elements/gel.c
@@ -17,6 +17,8 @@
 
 int update_GEL(UPDATE_FUNC_ARGS) {
 	int r, rx, ry;
+	if (parts[i].tmp>100) parts[i].tmp = 100;
+	if (parts[i].tmp<0) parts[i].tmp = 0;
 	for (rx=-2; rx<3; rx++)
 		for (ry=-2; ry<3; ry++)
 			if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry))