diff --git a/angelsrefining/src/sea-pump.lua b/angelsrefining/src/sea-pump.lua
index 419b9c348..b15ae16b1 100644
--- a/angelsrefining/src/sea-pump.lua
+++ b/angelsrefining/src/sea-pump.lua
@@ -204,7 +204,7 @@ function sea_pump:on_blueprint_setup(player_index)
   end
 
   -- type may be 'upgrade-item'
-  if blueprint.type ~= 'blueprint' then
+  if blueprint.type ~= "blueprint" then
     return
   end