diff --git a/source/Clean.js b/source/Clean.js
index 6590e2c..b03b3b8 100644
--- a/source/Clean.js
+++ b/source/Clean.js
@@ -178,7 +178,7 @@ var stylesRewriters = {
     }
 };
 
-var allowedBlock = /^(?:A(?:DDRESS|RTICLE|SIDE|UDIO)|BLOCKQUOTE|CAPTION|D(?:[DLT]|IV)|F(?:IGURE|IGCAPTION|OOTER)|H[1-6]|HEADER|L(?:ABEL|EGEND|I)|O(?:L|UTPUT)|P(?:RE)?|SECTION|T(?:ABLE|BODY|D|FOOT|H|HEAD|R)|UL)$/;
+var allowedBlock = /^(?:A(?:DDRESS|RTICLE|SIDE|UDIO)|BLOCKQUOTE|CAPTION|D(?:[DLT]|IV)|F(?:IGURE|IGCAPTION|OOTER)|H[1-6]|HEADER|L(?:ABEL|EGEND|I)|O(?:L|UTPUT)|P(?:RE)?|SECTION|T(?:ABLE|BODY|D|FOOT|H|HEAD|R)|COL(?:GROUP)?|UL)$/;
 
 var blacklist = /^(?:HEAD|META|STYLE)/;