Civil Defence Report Form Control Centre Counterpart CDF2 / CDF3

UPDATE: now confirmed to be a post-war Civil Defence Corps form. A, B and C are for Atomic, Biological and Chemical. GZ may be for Gas/Ground Zone. MFAU is for Mobile First Aid Unit, a term used by the Civil Defence Corps.

Some interesting documents have appeared for sale on eBay. Among the various documents is this Civil Defence Report Form Control Centre Counterpart CDF 2 & 3. An accompanying document, used for training lectures, details the use of the form. 

The seller also has a selection of post-war Civil Defence Corps documentation, and I wasn't entirely sure at first if it was a wartime document. After reviewing the form and the corresponding lecture notes, it looks to be from the Second World War (nothing on here about radiation etc), but I would be interested in the opinions of others.

​Most wartime documents tend to have, in tiny print in the gutter at the bottom, a series of printer's marks that usually include a month and year (for example, 3/44), but this form doesn't have one.

A couple of unknown items you perhaps can assist with:

• In the "Type of Attack", what do 'A.', 'B.', and 'C.' refer to?

• In the "Occurrence" section, what does 'GZ' stand for (I assume Z is Zone)?

Civil Defence Report Form Control Centre Counterpart CDF2 / CDF3

Lecture notes referring to Civil Defence Report Form CDF 2 and 3