Sinus Bradycardia. Sinus bradycardia is a heart rate below normal range for age. The rhythm originates in the sinus node, and ECG demonstrates a normal P-wave axis (upright in leads II and aVF) with a QRS following every P wave and a P wave preceding every QRS complex.
This means fitting the right tyres and for safety ensuring that they are inflated to the manufacturer's recommended pressure. The legal limit for minimum depth of the tread on your tyres is 1.6 millimetres, across the central  of the tread around the complete circumference of the tyre. For safety reasons it is recommended that you replace your tyres before the legal limit is reached. Many vehicle manufacturers recommend replacing at 3 millimetres. At 1.6 millimetres in wet weather it takes an extra two car lengths (8 metres) to stop at 50 mph than if your tread was 3 millimetres. A regular check of your tyres can help you to avoid 3 penalty points and 2,500 in fines for having tyres worn beyond the legal minimum limit on your vehicle.
The standards for rise, run and tread width vary slightly from area to area. You should find out what is acceptable in your area. Rise is usually 8 inches maximum, and runs are typically 9 to 11 inches minimum. The tread width is usually one inch more than the run.In some areas, this is called tread depth; in others it is head width. This is accomplished by adding a one-inch nosing to the tread.Problems with rise, run, tread width, uniformity and slope may be caused by. the way it was built. settlement or heaving. Stairs that have settled or heaved may have a slope.ise is usually 8 inches maximum, and runs are typically 9 to 11 inches minimum. The tread width is usually one inch more than the run. In some areas, this is called tread depth; in others it is head width.