diff --git a/tools/solar_helmet.lua b/tools/solar_helmet.lua
index 6493507..d6bdc92 100644
--- a/tools/solar_helmet.lua
+++ b/tools/solar_helmet.lua
@@ -22,7 +22,7 @@ local function onGlobalStep(player,inv,stack)
 	if stack:get_name()~="industrialtest:solar_helmet" then
 		return false
 	end
-	local amount=math.floor(minetest.get_node_light(player:get_pos())/2)
+	local amount=math.floor((minetest.get_node_light(player:get_pos()) or 0)/2)
 	if amount==0 then
 		return true
 	end