How to Clean and Handle Turbidity Meter Sample Vials Malaysia

Turbidity meters use light to evaluate suspended particles in water. Because the measurement is optical, fingerprints, scratches, droplets, bubbles and residue on the sample vial can interfere with the light path and affect the result.

For users of the Azovtes AE86065 turbidity meter, proper handling of the sample vial is essential for obtaining stable and repeatable readings.

Why Is the Sample Vial So Important?

The sample vial forms part of the optical measurement system. Light from the turbidity meter passes through the vial and water sample before reaching the detector.

The instrument may respond not only to particles in the water but also to:

Fingerprints
Dust
Water droplets
Scratches
Dried residue
Stains
Condensation
Air bubbles
Misaligned vials
Inconsistent sample volume

A clean-looking vial may still contain marks that affect a low-turbidity measurement.

Always Hold the Vial Correctly

Hold the sample vial by its upper section or cap whenever possible.

Avoid touching the optical measurement area because skin can leave:

Oil
Moisture
Fingerprints
Dust
Cosmetic or chemical residue

After filling the vial, wipe its exterior using a clean, soft and lint-free material.

Do not handle the clear optical surface immediately after cleaning it.

Inspect the Vial Before Every Test

Check the vial under suitable lighting for:

Cracks
Chips
Scratches
Cloudiness
Dried water marks
Residue
Discolouration
Damaged cap
Particles on the exterior

A cracked or heavily scratched vial should be removed from use.

Even small scratches can scatter light and cause the instrument to report higher or inconsistent turbidity.

How to Clean a Turbidity Sample Vial

A practical cleaning procedure is:

Empty the previous sample.
Rinse the vial with clean water.
Use a suitable mild cleaning solution if residue remains.
Clean without using abrasive tools.
Rinse thoroughly to remove detergent.
Perform a final rinse using suitable clean or deionised water.
Allow the vial to drain or dry in a clean environment.
Inspect it before use.
Store it with protection against dust and scratches.

The cleaning method should be compatible with the vial material and the sample being tested.

Detergent residue can affect the sample and may create bubbles, so thorough rinsing is essential.

Rinse the Vial With the Sample

Before taking a measurement, rinse the vial with a small amount of the water sample when the procedure allows.

This helps reduce contamination from:

Previous samples
Remaining rinse water
Storage conditions
Cleaning residue

Discard the rinse portion and then fill the vial with the test sample.

For regulated or laboratory methods, follow the approved sample-handling procedure.

Avoid Air Bubbles

Air bubbles scatter light and may be interpreted as turbidity.

Bubbles can appear when:

The vial is shaken vigorously
Water is poured too quickly
The sample is highly aerated
The vial contains detergent residue
Temperature changes release dissolved gases
The cap is tightened after excessive agitation

To reduce bubbles:

Pour the sample gently
Avoid vigorous shaking
Allow bubbles to rise
Tap the vial gently only when appropriate
Inspect the sample before inserting it
Keep the vial away from vibration

Do not wait so long that suspended particles begin settling before measurement.

Mix the Sample Without Creating Bubbles

Suspended particles may settle if the sample remains still. However, aggressive mixing can introduce bubbles.

Use gentle inversion or another approved mixing method to distribute particles evenly.

The goal is to obtain a representative sample while avoiding:

Foam
Bubbles
Particle breakdown
Excessive settling
Contamination

Use the same mixing method for repeated measurements to improve consistency.

Fill to a Consistent Level

Inconsistent sample volume may change the optical path or vial positioning.

Follow the meter’s specified filling procedure and avoid:

Underfilling
Overfilling
Liquid on the cap thread
Leakage onto the vial exterior
Trapping air below the cap

If a fill mark is provided, use it consistently.

Keep the Outside of the Vial Dry

Water droplets on the vial exterior can scatter or refract light.

Before insertion:

Inspect the complete optical surface.
Wipe away all droplets.
Remove fingerprints.
Check for condensation.
Confirm that the base is clean.
Handle only the upper section.

Avoid using tissue that leaves fibres or scratches the surface.

Prevent Condensation

Condensation may form when a cold sample is moved into warm, humid Malaysian air.

This can happen with:

Refrigerated samples
Chilled process water
Cold-room samples
Samples transported with ice
Air-conditioned laboratory testing

Condensation on the outside of the vial can interfere with measurement.

Allow the vial to reach a suitable condition according to the testing method, then wipe the exterior immediately before measurement.

Use the Same Vial Orientation

Glass and plastic vials may have slight optical differences around their circumference.

If the vial has an orientation mark:

Align it consistently with the meter
Insert it in the same direction for repeated tests
Avoid rotating it between measurements

Consistent vial orientation improves repeatability, especially at low turbidity levels.

Do Not Mix Calibration and Sample Vials Carelessly

Calibration standards should be protected from contamination.

Avoid:

Pouring used standard back into its bottle
Using a dirty vial for calibration
Mixing sample and calibration caps
Touching the optical surface
Leaving standards exposed
Using expired or contaminated standards

If reusable vials are used, maintain a clear cleaning and identification system.

Why Do Two Vials Give Different Results?

Different readings may occur because one vial has:

More scratches
A thicker wall
A different optical surface
Fingerprints
Residue
Different orientation
A different sample volume
More air bubbles

To investigate:

Fill both vials with the same well-mixed sample.
Clean both exteriors.
Remove bubbles.
Align them consistently.
Measure each vial several times.
Compare the results.

If one vial repeatedly produces a different result, remove it from precision testing.

What Causes an Unexpectedly High Turbidity Reading?

An unusually high result may be caused by:

Dirty vial
Scratched vial
Fingerprints
Bubbles
Condensation
Settled particles disturbed unevenly
Contaminated sample
Incorrect calibration
Stray light from improper vial positioning

Repeat the test using a clean vial and freshly prepared representative sample before concluding that the water condition has changed.

What Causes Poor Repeatability?

Poor repeatability commonly results from:

Different mixing methods
Particle settling
Changing sample volume
Vial rotation
Bubbles
Dirty optical surfaces
Inconsistent waiting time
Temperature changes
Sample changes between tests

Repeatability depends on controlling both the instrument and the sample-handling procedure.

Sample Vial Storage

Store turbidity vials:

In a clean protective case
Away from dust
Away from direct sunlight
Separate from abrasive tools
With caps protected
In a dry condition
Where they cannot roll or collide

Do not place unprotected vials together with probes, cables or metal accessories.

When Should a Vial Be Replaced?

Replace a sample vial when:

It is cracked or chipped
Scratches cross the optical area
Cloudiness cannot be removed
Chemical stains remain
The cap no longer seals properly
It repeatedly produces abnormal results
Its optical condition differs significantly from the other vials

Keeping spare compatible vials available reduces downtime.

Turbidity Measurement Checklist

Before pressing the measurement key, confirm:

The meter has been calibrated or verified
The sample is representative
The vial is clean
The exterior is dry
No fingerprints are visible
No air bubbles are present
The sample level is correct
The vial orientation is consistent
The cap is secure
Particles have not settled excessively

Good vial handling is one of the simplest ways to improve turbidity measurement quality.

Azovtes AE86065 Turbidity Meter Supplier Malaysia

MTM Precision supplies the Azovtes AE86065 and other water-quality testing instruments for drinking water, wastewater, laboratories, aquaculture and environmental monitoring across Malaysia.

Coverage includes Selangor, Kuala Lumpur, Johor, Penang, Perak, Melaka, Negeri Sembilan, Pahang, Kedah, Perlis, Terengganu, Kelantan, Sabah and Sarawak.

Contact MTM Precision

MTM Precision Sdn Bhd
Website: www.mtmpre.com.my
Email: mtmpre@yahoo.com
WhatsApp: 016-660 7346

Showroom & Service Centre

No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia

Contact MTM Precision for the Azovtes AE86065 turbidity meter and water-quality testing solutions in Malaysia.