9  Detecting a gas leak

9.1  General

Full gas detection functionality, including High Sensitivity Mode (HSM) (see section 9.4 Enhancing the image using High Sensitivity Mode (HSM) ), is available when the camera is set to Gas detection mode.
You can use the camera to also detect gas in Temperature measurements mode. With this setting, however, High Sensitivity Mode is not available.

9.2  Basic steps to gas detection

  • First adjust the focus. If the camera is out of focus, there is a risk of missing a gas leak.
  • The key to making the gas visible is enhancing the temperature difference between the gas cloud and the background. To obtain optimal contrast, try to find a suitable background by aiming the camera toward the target from different angles.
  • Motion of the gas, e.g., caused by wind, makes the gas cloud easier to see.
  • Using High Sensitivity Mode (HSM) can improve the detection of gas leaks, especially when they are small or low in concentration.
  • The camera automatically adjusts the temperature scale. Use this mode first, but do not hesitate to set the scale manually. By centering on the temperatures around the background of the gas, you can make the gas appear more clearly.
  • Selecting a different color palette can make it easier to see the gas cloud.

9.3  Adjusting the camera focus

It is very important to adjust the focus correctly. If the camera is out of focus, there is risk of missing a gas leak.

9.3.1  Manual focus

You can adjust the focus manually by rotating the focus ring. For more information, see section 21.4.1 Manual focus .

9.3.2  Autofocus

You can autofocus the infrared camera by pushing the Autofocus button. For more information, see section 21.4.2 Autofocus .

9.3.3  Continuous autofocus

The infrared camera can be set up to perform continuous autofocusing. For more information, see section 21.4.3 Continuous autofocus .

9.4  Enhancing the image using High Sensitivity Mode (HSM)

9.4.1  General

High Sensitivity Mode (HSM) is an adjustment method specifically designed for gas detection applications. By enhancing the thermal sensitivity of the camera, HSM can improve the detection of gas leaks, especially when they are small or low in concentration.
One feature of HSM mode is to make motion, such as moving gas, more visible in the image. This is achieved by an image-subtraction video-processing technique. This HSM feature subtracts a percentage of individual pixel signals from frames in the video stream from subsequent frames, thus enhancing the differences between frames, which makes a moving gas cloud stand out more clearly in the resulting images.

9.4.2  Procedure

To enable High Sensitivity Mode (HSM), do the following:

1

Push the navigation pad to display the menu system.

2

Select icon (Image mode) and push the navigation pad. This displays a submenu.

3

Select icon (HSM) and push the navigation pad.

9.5  Adjusting the temperature scale

By default, the camera continuously adjusts the image for the best image presentation. Use this automatic mode first, but do not hesitate to adjust the temperature scale of the infrared image manually. For more information, see section 11 Infrared image adjustment .

To adjust the temperature scale, do the following:

1

Touch the soft button icon to enter manual image adjustment mode.

2

Do one or more of the following:

  • To simultaneously change the temperature scale minimum and maximum limits, place your finger on the screen and move it up/down.
  • To change the minimum limit or the maximum limit, do the following:
    1. Touch the maximum or minimum temperature that you want to change.
    2. Place your finger on the screen and move it up/down to change the value of the highlighted temperature.
  • To enhance the details for a certain point of interest in the image, touch the point on the screen. The image will be auto-adjusted based on the thermal content of the area around the touched point.
3

To prevent further unintentional adjustments, you can lock the touch screen.

  • To lock the screen, touch the icon icon.
  • To unlock the screen, touch the icon icon.

9.6  Changing the color palettes

You can change the color palette that the camera uses to display different temperatures. A different palette can make it easier to see a gas cloud. For more information, see section 12 Color palettes .

To change the color palette, do the following:

1

Push the navigation pad to display the menu system.

2

Select icon (Color) and push the navigation pad. This displays a submenu.

3

Use the navigation pad to select a different palette.

4

Push the navigation pad to confirm and exit the menu mode.

9.7  General instrument check

The following general instrument check process ensures that the camera can detect the intended gas compounds with the same sensitivity as when originally manufactured.
  1. Make sure that the camera powers on.
  2. Make sure that the camera produces a live infrared image.
  3. Make sure that the camera does not report any error messages on startup.
  4. Make sure that the camera focuses properly.
  5. Make sure that the camera is able to engage HSM mode.