Introduction
In this blog post, we will be discussing a quick tip called the 70 Rule. This rule can come in handy when you need to estimate the depth of a pipe using a locator.
Whether you are questioning the accuracy of your locator's depth reading or using an older locator that does not provide depth information, the 70 Rule can help you get a good estimate of the depth.
The 70 Rule Explained
To understand the 70 Rule, let's walk through an example. Imagine that you are trying to locate a gas line using a locator.
You have successfully located the pipe, and your peak reading is at a certain point. Now, you want to determine the depth of the pipe.
The first step is to place the locator on the ground. This is crucial for accurate readings. The 70 Rule gets its name because you will be moving the locator to the left and right until you reach 70% of your signal strength number.
For ease of explanation, let's assume that your signal strength number is 50. To make things simpler, adjust your gain to increase or decrease the signal strength until it reaches around 50. It doesn't have to be exact, but somewhere close to 50.
Now, the calculation comes into play. 70% of 50 is 35. So, you will move the locator to the left until you see a reading of 35. Remember, this doesn't have to be perfect, but try to get it close to 35. Mark this spot for reference.
Next, move the locator back to the center of the pipe and start moving it to the right. Continue moving it until it hits 35 again. Mark this spot as well.
Verifying the Depth
Now that you have marked the left and right spots, it's time to verify the depth using the 70 Rule.
The rule states that the distance between the two marks you made, whether horizontally or vertically, represents the depth of the pipe. To verify the depth, grab a tape measure and measure the distance between the two marks.
In our example, it's giving us about 35 inches, which is just under three feet. This measurement serves as a good estimate of the depth, although not perfect.
Conclusion
The 70 Rule is a handy technique to estimate the depth of a pipe when using a locator.
Whether you are questioning the accuracy of your locator's depth reading or using an older locator that does not provide depth information, the 70 Rule can give you a reliable estimate.
Remember to place the locator on the ground and adjust your gain to get the signal strength around 50. By following the steps of the 70 Rule and marking the left and right spots, you can determine the depth of the pipe.
While the 70 Rule may not provide an exact measurement, it can give you a good estimate to work with. This knowledge can be particularly useful in situations where precise depth information is not readily available.
So, the next time you find yourself needing to estimate the depth of a pipe, remember the 70 Rule and use it to your advantage.