diff --git a/items/allengineeringlights.items b/items/allengineeringlights.items
deleted file mode 100644
index 85204c3..0000000
--- a/items/allengineeringlights.items
+++ /dev/null
@@ -1 +0,0 @@
-Switch  all_engineering_lights       "All Engineering Lights"         <lightbulb> (engineering)
diff --git a/items/alllights.items b/items/alllights.items
deleted file mode 100644
index 83964dd..0000000
--- a/items/alllights.items
+++ /dev/null
@@ -1 +0,0 @@
-Switch  all_lights       "All Lights"         <lightbulb> (level2)
diff --git a/items/critical.beamer.items b/items/critical.beamer.items
new file mode 100644
index 0000000..79b4d0a
--- /dev/null
+++ b/items/critical.beamer.items
@@ -0,0 +1,22 @@
+Switch  chill_zone_beamer
+    "Beamer"
+    (chill_zone)
+String chill_zone_beamer_input          "beamer input"      (chill_zone)
+// please help: beamer current state can be optained like this:
+//wget -qO - 'http://10.2.113.7/tgi/return.tgi?query=info' |awk -F'[<>]' '/<info>/{print substr($3,33,2)}'
+// the awk extracts the info. It is in format '<return>NG</return>' or '<return><info>data</info></return>
+//NG = off
+// from data, the interesting part is chars 33 and 34
+//                                vv
+//2a3139c616503735303000000048e60102ac0c010076
+//00=no signal
+//01=VGA1
+//02=DVI (slideshow)
+//03=composite
+//04=s-video
+//05=component
+//09=VGA2
+//11=LAN
+//12=USB A (presentation to go)
+//13=USB B (WTF?)
+//15=hdmi2 (chromecast)
diff --git a/items/critical.chromecast.items b/items/critical.chromecast.items
new file mode 100644
index 0000000..76b86e7
--- /dev/null
+++ b/items/critical.chromecast.items
@@ -0,0 +1,9 @@
+// If ChromeCast doesn't work you have to link this item with the Chromecast channel manually
+String  chill_zone_chromecast_appid
+    "Chromecast AppId [%s]"
+    { channel="chromecast:chromecast:b000d809ccb35a409a3dd3d14e0fbf08:appId" }
+
+// If ChromeCast doesn't work you have to link this item with the Chromecast channel manually
+String  chill_zone_chromecast_status
+    "Chromecast Status [%s]"
+    { channel="chromecast:chromecast:b000d809ccb35a409a3dd3d14e0fbf08:statustext" }
diff --git a/items/readme.txt b/items/readme.txt
index b214510..fe7b7bc 100644
--- a/items/readme.txt
+++ b/items/readme.txt
@@ -1,5 +1,9 @@
-Your item definitions go here.
-All items files have to have the ".items" file extension and must follow a special syntax.
+Naming conventions
+------------------
 
-Check out the openHAB documentation for more details:
-https://www.openhab.org/docs/configuration/items.html
+In `uncritical.items` you'll find all the items that will not trigger any rules
+if you update the file. In `critical.<object>.items` you will find items that
+will probably trigger rules when you update the file.
+
+The separation was made so that uncritical items can be safely modified without
+triggering any rules.
\ No newline at end of file
diff --git a/items/statuslights.items b/items/statuslights.items
deleted file mode 100644
index c3487c5..0000000
--- a/items/statuslights.items
+++ /dev/null
@@ -1 +0,0 @@
-Switch  all_status_lights       "All Status Lights"         <lightbulb> (engineering)
\ No newline at end of file
diff --git a/items/level2.items b/items/uncritical.items
similarity index 70%
rename from items/level2.items
rename to items/uncritical.items
index ef8d662..d57ca9a 100644
--- a/items/level2.items
+++ b/items/uncritical.items
@@ -24,46 +24,6 @@ Switch  engineering_ceiling_phone_flash "Ceiling Phone Flash"   <lightbulb> (eng
 Switch  area42_status_lamp              "Status Lamp"           <lightbulb> (area42)        { channel="mqtt:topic:mosquitto:area42_status_lamp:power" }
 Switch  lab_soldering_table             "Soldering table"       <lightbulb> (lab)           { channel="mqtt:topic:mosquitto:lab_soldering_table:power" }
 
-
-
-// ----------------------------------------------------------------------------
-
-// If ChromeCast doesn't work you have to link this item with the Chromecast channel manually
-String  chill_zone_chromecast_appid
-    "Chromecast AppId [%s]"
-    { channel="chromecast:chromecast:b000d809ccb35a409a3dd3d14e0fbf08:appId" }
-
-// If ChromeCast doesn't work you have to link this item with the Chromecast channel manually
-String  chill_zone_chromecast_status
-    "Chromecast Status [%s]"
-    { channel="chromecast:chromecast:b000d809ccb35a409a3dd3d14e0fbf08:statustext" }
-
-// ----------------------------------------------------------------------------
-
-Switch  chill_zone_beamer
-    "Beamer"
-    (chill_zone)
-String chill_zone_beamer_input          "beamer input"      (chill_zone)
-// please help: beamer current state can be optained like this:
-//wget -qO - 'http://10.2.113.7/tgi/return.tgi?query=info' |awk -F'[<>]' '/<info>/{print substr($3,33,2)}'
-// the awk extracts the info. It is in format '<return>NG</return>' or '<return><info>data</info></return>
-//NG = off
-// from data, the interesting part is chars 33 and 34
-//                                vv
-//2a3139c616503735303000000048e60102ac0c010076
-//00=no signal
-//01=VGA1
-//02=DVI (slideshow)
-//03=composite
-//04=s-video
-//05=component
-//09=VGA2
-//11=LAN 
-//12=USB A (presentation to go)
-//13=USB B (WTF?)
-//15=hdmi2 (chromecast)
-
-
 // ----------------------------------------------------------------------------
 
 //Switch  chill_zone_meaow "Meaow" {channel="exec:command:meaow:run"}
@@ -88,4 +48,9 @@ Rollershutter chill_projection_screen "Projection Screen"
 
 String IRCode		"IR Code"			{ channel="mqtt:topic:mosquitto:irremote:ir_code" }
 String proxyIR
-         
+
+// ----------------------------------------------------------------------------
+
+Switch  all_lights              "All Lights"                <lightbulb> (level2)
+Switch  all_status_lights       "All Status Lights"         <lightbulb> (engineering)
+Switch  all_engineering_lights  "All Engineering Lights"    <lightbulb> (engineering)