A Fireman badge but what exactly?

[Watchdog]

Good afternoon gents,

I have had this badge for years but never defined it completely.

I believe it is a fireman qualification of some kind but the symbology seems to be somewhat "busy";

I say fire service because of the helmet and what appears to be a fire nozzle but the nozzle is crossed with a rifle so does that indicate a military connection? I am also assuming that one of the letters "P" in PDP on the rhomboid is for "Pozharnik"?

The white rhomboid background with the blue border suggests in the first instance an academy badge but does the blue border have meaning?

The outer "frame" of the badge is a stylised cog wheel on the left with a wheatsheaf on the right suggesting industry and agriculture respectively. Or perhaps the two together indicate "Labour" as with some other Soviet awards.

It is obviously Soviet Russian because of the CCCP legend (albeit in unusual arrangement)
The main device is made in two pieces pinned together and it appears to be bronze rather than brass, a higher quality of metal suggesting greater status than a rank and file issue.

It is serial numbered suggesting an individual award specific to a qualification of some kind.

Can anyone please fully identify this badge for me?

I am looking for; Branch of service, nature of qualification and period of issue. Any other info would be a bonus!!



Regards

Mark

PS I am also intrigued by the inclusion of "No11" on the screw plate. Is this a factory or perhaps a pattern number?