Maintaining a proper level of air pressure in the tires of an automobile is significantly important to the safety of the passengers. Improper tire pressure can lead to misalignment and blowouts. Use a tire gauge to ensure the tires are inflated to the proper air pressure. A tire gauge measures the air pressure in a tire. To ensure the tire gauge gives you an accurate reading, calibrate the tire gauge before use. You will need another person to help you calibrate the tire gauge.
Unravel the hose and stretch it out on the ground, making sure to undo any kinks.
Extend the measuring tape beside the hose.
Draw a horizontal line on the hose with a marker at every meter of length. Make the lines at the 10-meter, 20-meter and 25-meter points darker than the rest.
Carry a bucket of water, a funnel and the hose to the top of a 25-meter building. Have another person stand at the bottom of the building, holding the tire gauge.
Hold the end of the hose with the 25-meter mark and gently drop the other end of the hose down to the ground. Have the other person grab the end of the hose and attach the tire gauge.
Straighten the hose as much as you can, leaving no kinks.
Insert the funnel into the end of the hose and slowly fill the hose with water to the 1-meter mark.
Have the person on the ground read the tire gauge. It should read 1.4233 pounds per square inch (PSI). If it does not read 1.4233 PSI, have the person on the ground adjust the calibration on the tire gauge until it reads 1.4233 PSI. Calibrate the tire gauge by following the manufacturer's instructions; many models require you to turn the dial at the head of the gauge until the reading is accurate. Once the gauge reads accurately, continue the calibration process.
Slowly fill the hose with water to the 10-meter mark. Have the person on the ground read the tire gauge, which should read 14.2 PSI. If it does not read 14.2 PSI, have the person on the ground adjust the calibration of the tire gauge until it reads accurately.
Slowly fill the hose with water to the 20-meter mark. Have the person on the ground read the tire gauge, which should read 28.4 PSI. If it does not read 28.4 PSI, have the person on the ground adjust the calibration of the tire gauge until it reads accurately.
Slowly fill the hose with water to the 25-meter mark. Have the person on the ground read the tire gauge one last time. The measurement should read 35.5 PSI. If it does not, have the person on the ground adjust the calibration of the tire gauge until it reads accurately. At this point, the tire gauge should be properly calibrated. If the tire gauge can not be calibrated to the accurate reading, the gauge is likely faulty.
