I want Mark Drakeford and the Welsh Government to scrap the 50 mph speed restriction around Newport and the Brynglas tunnels.

I speak as a qualified Aeronautical Engineer of some years; an ex-rally co-driver, and Motoring Correspondent. 

There are often signs on this stretch advising that to “Slow down, Pollution kills”. Yes, pollution kills, but the 2 phrases are not linked, as this speed limit shows. Anyone who has travelled this route would know, as you slow the traffic down there is a corresponding ‘bunching’ of vehicles, which actually increases pollution. They are confining more vehicles, (than would otherwise be), into a limiting space. 

Additionally, if you reduce speed, invariably you need to change down a gear. On automatic vehicles, (including vast capacity engined articulated lorries) this change down is carried out without the drivers’ consent, and cannot be over-ridden. I will spare you the maths, but suffice to say my vehicle exhausts an extra 1,050,000cc of exhaust pollution for the distance of the 50 mph zone than if I was travelling at 70mph. So where is the pollution reduction Mr Drakeford?

In short, you are causing traffic to spend an extra 2 minutes minimum, at a higher RPM, to travel the same distance, (7.5 miles) than would normally be necessary, thereby  actually increasing pollution. It is apparent that the only people gaining from this exercise are the ‘pollution monitors’, and advisers. (we have been here before). I wonder how much these people are not (allegedly), being paid to hoodwink the Government and the people of Wales and other nations?

Moreover, there is a phenomenon, which I shall call ‘Concertina Braking’, in which the driver in front applies the  brakes to slow for the 50 mph limit; the driver behind brakes a little firmer; the driver behind them then brakes even more, and before you know it, the traffic is at a near standstill churning out the dreaded pollution for no distance travelled. Just look how the traffic clears at Tredegar Park heading west, and at Coldra heading east when the restrictions are eased. I cannot be the only one to observe this. 

You will note I am doing my utmost to avoid the mention of traffic accidents, (and subsequent fatalities – out of respect for the families), but I feel it is justified to point out that there have been several collisions on this stretch since the introduction of the limit, and sadly, indeed, many recent fatalities. These RTA’s not only can be caused by inattentive drivers missing the initial braking, but by having to constantly look down at the speedo, simply to avoid a fine and 3 points. All it takes is a second of your eyes away from the road and you will have travelled more than 22Mtrs, (nearly 75 feet). Think of it this way, “Try-line to the 22Mtr.line”, in half the time it took you to read that.

There is also the less common cause of the frustrated ‘lane-hoppers’, constantly accelerating and braking. Ergo, (in addition to a potential accident cause),  more pollution.

By the way, CO2 is not a pollutant, it’s plant food. Plants breathe this in and ‘exhale’ oxygen. If you really want to get technical, our atmosphere is less than 0.04% CO2. yet humans exhale 4.00% CO2. Consequently, to instantly save 3.96% CO2… simply stop breathing. By the same token, you may need to consider banning wood burning stoves; animals, and indeed humans, where in certain areas, (EG train stations),we breathe in up to 15% human skin.

As an aside I’d like to draw your attention to the flashing speed ‘advisory’ matrix signs, sometimes showing “40mph” and “queues likely”, (I wonder why?) on this stretch. And that what this sign means. It is an ‘advisory limit’. Put simply, if a sign in a red ring, it's COMPULSORY. if it's on a black matrix sign it's ADVISORY. So, you have no LEGAL requirement to reduce your speed to this figure.

I will ignore the fact that even though your speedo will indicate 50 mph, you may  be travelling up to 5 mph less, but you are all aware of this now. Speedometers are designed this way.

Thank you for your time.