No, he is not a 'Sir'
The Order of the British Empire has 6 ranks, 2 of which entitle the holder to put ‘Sir’ or ‘Dame’ in front of their name.
OBE – Officer of the Order of the British Empire, is the second rank of the order and is the one that those who have performed very worthy service are admitted to. The holder uses the letters OBE after their name, for example Miss Jane Smith OBE.
KBE/DBE – Knight/Dame Commander of the Order of the British Empire, this is the 2nd from highest rank in the order and is awarded usually for long and respected service in an individual’s field. The holder typically will use the title of ‘Sir’ if male in front of their first name and ‘Dame’ if female. KBE is male and DBE is for females.
GBE – Knight/Dame Grand Cross of the Order of the British Empire, this is the top rank in the order and typically only one or two of these are given out a year – they’re extremely rare and are given out for exceptional service. The holder uses the title of Sir (male) or Dame (female).
http://royalcentral.co.uk/blogs/insight/a-guide-to-the-order-of-the-british-empire-21224