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There are two outputs I am interested in finding out about on my WOF sheet. I need a WOF every 6 months so this information may help with future maintenance or purchases.

One is the Tyre tread reading - at what reading is it a fail- I have a couple of 2's- should I be looking to replace very soon. Both 2s are on the back.

The other is the Brake performance reading, I have read about percentages but my readings are just figures. There are figures for Axle 1 Left and Right, Axle 2 Left and Right and Park Brake Left and Right. Must Left and right be equal or there about and is there
a value at which it fails for example a value low like 4 or 5 or a value high like 20. What do the numbers mean?

Hi there,
The minimum tyre tread depth to pass a wof is 1.5mm below this is a fail. So at 2mm you will need to replace the tyres soon.
Now the brake readings will vary, on the method used to test the brakes. They can be a Tappley meter, or rollers/ rolling road or others. And can have percentage figures from all four brakes/wheels, which combine to give overall braking performance.
This is the wording from the wof rules for modern vehicle brakes.

"The service brake of a vehicle or vehicle combination that is operated on a hard, dry, level surface that is free of loose material and without assistance from the compression of the engine or other retarders must operate in the following manner:
a) A service brake that acts on each wheel must stop the vehicle within a distance of 7m from a speed of 30km/h (average brake efficiency of 50%)".

Thanks I will start to look out for some tyres.

Yes I read the wof rules this morning but could not relate them to the figures on the sheet.
The car was tested on a rolling road with the huge gauges along side.

This would be taken on the brake roller machine, it takes a reading of brake force for each wheel, calculates the imbalance and efficiency based on vehicle weight. Then identifies a pass or fail from that information.