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Water Quality Testing Malaysia

The Complete Guide to Water Quality Testing

Water quality testing is very useful in ensuring the safety and suitability of water, whether for household or industrial purposes. It entails a series of specific steps to determine the physical, chemical, and biological composition of water. By examining varying parameters, such as temperature, pH, dissolved gas and contaminants, water quality tests provide valuable information regarding the quality of different water sources.


In this article, we will explore water quality testing procedures in detail, examining various aspects such as sampling techniques, physical and chemical parameter measurements, biological indicators, laboratory analysis, and data interpretation. By delving into these key components of water quality testing, we aim to provide a comprehensive understanding of how water quality is assessed and monitored to ensure its safety and suitability for different uses.

Sampling (Water Sample Collection)

Sampling is the initial stage of water quality testing and is crucial for obtaining accurate and representative results. Proper sampling techniques are essential to ensure the reliability of the data collected. Here's an overview of the sampling process:

  1. Selection of Sampling Points: Sampling points are strategically chosen based on factors such as the location of potential contaminants, the intended use of the water, and regulatory requirements. Common sampling points include rivers, lakes, streams, wells, groundwater sources, and before & after filter system.

  2. Sampling Equipment: Sterile bottles or containers are used to collect water samples to prevent contamination. The containers are typically made of inert materials such as glass or high-density polyethylene (HDPE) and are thoroughly cleaned and rinsed before use to eliminate any residues that could affect the sample.

  3. Sampling Techniques: Various sampling techniques are employed depending on the source of water being sampled. For surface water bodies such as rivers and lakes, samples may be collected using a sampling pole, bucket, or grab sampler. Groundwater samples are often collected using a pump or bailer. For tap water, samples are typically collected directly from the tap after flushing the line to remove stagnant water.

  4. Sampling Procedures: Sampling procedures follow specific guidelines to ensure consistency and accuracy. These may include the use of standardized protocols established by regulatory agencies or international organizations. Samples are collected at designated depths or locations, and care is taken to avoid cross-contamination between samples.

  5. Preservation and Handling: Once collected, water samples are preserved and handled according to established protocols to maintain sample integrity.

  6. Chain of Custody: Chain of custody procedures are implemented to document the handling and custody of water samples from collection to analysis. This ensures traceability and accountability throughout the testing process, particularly for regulatory compliance and legal purposes.


By adhering to proper sampling techniques and protocols, water quality professionals can obtain reliable and representative samples for analysis, enabling accurate assessment of water quality and informed decision-making regarding water management and treatment strategies.

Physical parameters
Physical parameters are fundamental indicators used to assess the appearance and clarity of water, providing initial insights into potential water quality concerns. Here's a breakdown of common physical parameters measured during water quality testing:

  1. Turbidity: Turbidity refers to the cloudiness or haziness of water caused by suspended particles such as sediment, organic matter, or plankton. High turbidity levels can reduce light penetration, affecting photosynthesis and aquatic plant growth. It can also indicate soil erosion, wastewater discharge, or algal blooms, which may impair water quality and ecosystem health.

  2. Color: Unusual coloration in water, such as brown, green, or red hues, may indicate the presence of natural substances like dissolved organic matter or algae pigments. However, abnormal coloration can also result from industrial discharges, agricultural runoff, or contamination from substances like heavy metals or chemicals.

  3. Suspended Solids: Suspended solids refers to small solid particles which remain in suspension in water as a colloid or due to motion of the water. These include dust, sand, organic and in-organic substance which are measured in terms of micron.


By monitoring these physical parameters, water quality professionals can identify potential issues, track changes in water quality over time, and prioritize management actions to protect and restore aquatic ecosystems and ensure safe drinking water supplies. Early detection of abnormalities in temperature, turbidity, color, odor, or taste enables timely intervention to mitigate impacts on human health and the environment.

Chemical parameters
Chemical parameters play a vital role in assessing water quality by providing insights into the composition and contamination levels of water. Here's an overview of key chemical parameters tested during water quality analysis:

  1. pH: The pH level measures the acidity or alkalinity of water on a scale from 0 to 14, with 7 considered neutral. pH affects the solubility of substances and influences chemical reactions, nutrient availability, and the survival of aquatic organisms. Extreme pH levels can indicate pollution from sources such as acid rain or industrial discharges.

  2. Total Dissolved Solids (TDS): TDS represents the total concentration of inorganic and organic substances dissolved in water, including salts, minerals, metals,chlorine and other compounds. Elevated TDS levels can affect water taste, appearance, and suitability for drinking or agricultural use. Sources of TDS include natural weathering of rocks and soils, agricultural runoff, industrial discharges, and wastewater effluents.

  3. Nutrients: Nutrient testing focuses on measuring levels of essential nutrients such as nitrogen and phosphorus, which are critical for plant growth and aquatic ecosystem health. Excessive nutrient concentrations, particularly in the form of nitrates and phosphates, can lead to eutrophication, harmful algal blooms, and oxygen depletion in water bodies.

  4. Heavy Metals: Heavy metals, including iron, mercury, arsenic, cadmium, and chromium, are tested due to their toxicity even at low concentrations. These metals can accumulate in aquatic ecosystems, posing risks to human health and aquatic life. Sources of heavy metals include industrial discharges, mining activities, and urban runoff.


Biological parameters

Biological parameters play a critical role in assessing water quality by providing information about the presence of microorganisms, including bacteria, viruses, and parasites.

Laboratory Analysis

After sample collection, the water samples are carefully transported to a laboratory for thorough analysis. Companies such as Delco have Certified laboratories with specialized equipment and techniques to carry out accurate and precise measurements.

Data Interpretation

After the laboratory analysis concludes, the next step is data interpretation. During this phase, the test results are scrutinized and compared against established regulatory standards or guidelines to assess compliance.

The goal of data interpretation is to pinpoint any potential water quality concerns or health risks present in the tested samples. If the analysis reveals that the water quality falls short of the mandated standards, it's imperative to take prompt and appropriate action to rectify the identified issues and safeguard the water's safety.

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Delcol is the leading brand name for water dispensers, water filters, reverse osmosis systems and water treatment products be it for household, corporate or industrial applications. We provide 30,000 businesses across Malaysia with clean water and quality water filtration systems.

Delcol is headquartered in Malaysia's capital city, Kuala Lumpur with offices in Kota Kinabalu, Sabah.


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22, Jalan Kencana 20, Taman Kencana, 56100 Kuala Lumpur, Wilayah Persekutuan,


(03) 4297 3388 | (03) 4285 2243

(017) 300 7835 | (012) 335 8509 | (012) 611 2955


Ground Floor, Lot 48, Light Industrial Building, Bandar Baru Penampang, 88200 Kota Kinabalu, Sabah

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