How To Check Turbidity of Water Sample | Turbidity Test Using Nephelometer | Eco Paryavaran

Summary

In this video, the process of measuring turbidity using a digital nephrometer from Electronics India, model 341, is explained. The equipment is calibrated with certified reference materials (CRM) of different turbidity levels, such as 0.11, 10, 20, 40, and 100 NTU. After calibration, the instrument is used to measure the turbidity of water samples. The measured turbidity values are recorded in a logbook, including relevant details like date, time, sample name, code, test parameters, and the analyst's information.

Takeaways

• 😀 The instrument used for turbidity measurement is called a nephrometer, specifically the digital nephrometer model 341 from Electronics India.
• 😀 Calibration of the instrument is done using turbidity CRMs (Certified Reference Materials) with known NTU values.
• 😀 A calibration button on the nephrometer allows the user to perform calibration steps.
• 😀 The blank solution is set to zero before calibration to ensure accurate measurements.
• 😀 Various CRMs (e.g., 0.11, 10, 20, 40, 100 NTU) are used for calibrating the nephrometer at different turbidity levels.
• 😀 The turbidity CRM used for calibration has a value of 1000 NTU, and the instrument is calibrated using diluted versions of it.
• 😀 After calibration, the instrument's reading is verified using a 50 NTU standard CRM to ensure accuracy.
• 😀 Once calibration is completed, the sample is placed into the measuring cell, wiped clean, and tested for turbidity.
• 😀 The turbidity reading of the sample is recorded, with typical results in the range of 2.3 to 2.5 NTU.
• 😀 The turbidity results, along with the date, time, sample name, test parameters, and the analyst's details, are logged in a logbook.

Q & A

What is the instrument used to check the turbidity of the samples?

The instrument used to check the turbidity of the samples is a nephrometer, specifically the digital nephrometer model 341 from Electronics India.

What does the button on the nephrometer do?

The button on the nephrometer is used for calibrating the instrument and setting the blank solution to zero.

What are CRM standards used for in this process?

CRM (Certified Reference Material) standards are used to calibrate the nephrometer. These include a 1000 NTU turbidity standard, as well as diluted CRMs at concentrations of 0.11, 10, 20, 40, and 100 NTU.

How is the calibration of the nephrometer done?

Calibration of the nephrometer is done by using the CRM standards and the calibration button on the instrument. The blank solution is first set to zero, and then the instrument is calibrated with the different CRM standards.

What should be done before taking a sample reading with the nephrometer?

Before taking a sample reading, the sample should be shaken and wiped off, and the sample should then be placed in the cell of the nephrometer.

How is the turbidity of the sample recorded?

Once the sample is placed in the nephrometer, the turbidity is measured, and the reading is noted down in the instrument logbook, including the date, time, sample name, code, test parameter, and the analyst's name.

What turbidity value was recorded for the standard sample used during the calibration?

The turbidity value recorded for the 50 NTU standard sample during calibration was 0.1.

What details are required to be mentioned in the instrument logbook for turbidity measurements?

In the instrument logbook, the following details should be recorded: the date, time, sample name, code, test parameter, and the analyst who conducted the test.

What is the role of the CRM solutions with different NTU values?

The CRM solutions with different NTU values (e.g., 0.11, 10, 20, 40, and 100 NTU) are used to calibrate the nephrometer across a range of turbidity values, ensuring accurate readings for different levels of turbidity.

Why is it important to set the blank to zero before calibration?

Setting the blank to zero is crucial because it ensures that any turbidity readings obtained are measured relative to a clean, clear solution, preventing interference from background turbidity.