Cant remember how to post pictures here,apologies.I have a very dodgy shoulder,but what I did is get a male coupling,and bolt it on to the catwalk,easier to drain the air in a couple of seconds,and virtually no resistance from red suzie. Tell me how to post pics and ill show you what i mean. 
Engine off, in gear, handbrake off !
This is what happened to one of our Rochdale drivers when he hadnât turned the taps on and what was left of the hairdressing salon at 6 am after he drove through it ! The geezer in the house next door got knocked out of bed then he couldnât open his fronât door cause the impact had âtightenedâ his wall up a bit ! Good job it never happened during the salon opening hours
Those airline taps became obsolete when every airline got âseal when disconnectedâ valves on.
There was quite a long change-over period, when many trailers had self sealing airlines, but some didnât.
I think the last time I saw a unit with taps on the airlines was about 96.
Also, many units had 3 airline connections. The third one was coloured blue and was for the trailer brake, normally operated by a lever on the dash, commonly known as the"dead mans handle".
These finally disappeared a little bit later than airline taps. These days, the hand brake lever covers the trailer brake lever. The travel between âOffâ to the âOnâ latch operates the trailer brakes. Over the lock puts all brakes on when parked. I was driving for BRS/Exel Logistics/NFC back then, antiquated units and trailers. I had an N reg ERF EC14 
, producing 340bhp 
until 98, when I was paid off from the British Steel contract (BSD).