Biocide Selection studies (Kill studies)

Validate and Optimize Chemistry Before You Deploy It

A kill selection study (also known as a biocide selection study) is a controlled laboratory evaluation designed to determine which biocide chemistry performs most effectively against the microbial population present in your specific system.

Rather than relying on inconsistent or historical treatment programs, OSP tests multiple candidate biocides in your water source to measure real-world performance. The goal is simple: Identify the chemistry and dosage that delivers the most reliable microbial control under your operating conditions, with the fluids you are using.

Why Kill Studies Matter

Microbial communities vary significantly between basins, facilities, water sources, and fuel systems. A biocide that performs well in one system may underperform in another due to:

Differences in microbial composition
Biofilm presence
Salinity and TDS levels
Temperature
Chemical compatibility
Organic load

Without validation, asset owners risk:

Chronic underdosing
Ineffective treatment
Persistent souring or corrosion
Increased asset degradation

A selection study eliminates guesswork by generating data-driven comparisons between treatment options.

Industries We Serve

Kill studies are valuable wherever microbial risk intersects with asset integrity, production reliability, or regulatory exposure. Whether operating upstream, midstream, downstream, or in finished fuels and industrial water systems, this service is designed for asset owners who need validated treatment performance — not assumptions.

— Oil & Gas

New or untested water sources
Persistent souring or corrosion
Inconsistent biocide performance
Asset integrity and risk management programs
Reservoir and produced water systems

— Fuels

Above and below-ground storage tanks
Terminals and distribution systems
Water bottoms treatment
Fuel systems at risk of microbial contamination

— Industrial Water Treatment

Cooling towers
Process water systems
Biofouling and slime control
Highly regulated environments

How ATP Testing Supports Kill Studies

ATP (Adenosine Triphosphate) testing plays a central role in biocide selection studies by providing rapid, quantitative measurement of active microbial biomass before and after treatment. Because ATP reflects living microbial activity, it allows precise evaluation of how effectively each candidate biocide reduces microbial load.

By comparing ATP reductions across:

Multiple chemistries
Different dosage rates
Varying exposure times

OSP determines which product achieves the greatest microbial kill under simulated field conditions. Rapid ATP turnaround makes it ideal for performance comparisons and study efficiency.

How the Process Works

1. Discovery Call:
OSP conducts an initial consultation to understand system history, operational challenges,  and treatment goals.

2. Sample Kit Delivery:
A testing kit is sent directly to the client with clear instructions for sample collection.

3. Laboratory Analysis:
Samples are analyzed using ATP testing.

4. Interpretive Reporting:
OSP delivers a detailed but clear report that includes: Microbial identification, Functional risk interpretation, Operational implications, and Treatment considerations.

5. Collaborative Review & Treatment Planning:
Unlike standard labs that provide raw data dumps, OSP’s reporting is collaborative and interpretive. After results are delivered, OSP works directly with clients to diagnose the issue, refine or build a treatment plan, optimize chemistry selection, and reduce risk moving forward. The goal isn’t just analysis but an actionable strategy.

From Diagnostics to Optimization

Biocide Selection Studies are often paired with:

DNA Testing (to identify and quantify microbial populations)
Water chemistry analysis

Together, these services support a complete microbial risk management strategy.

Request a Kill Study

If you want to optimize your treatment program, reduce chemical waste, and protect critical infrastructure

What Makes OSP Different

Most labs provide data. OSP provides interpretation and collaboration.

Reports are not generic or automated, offering targeted analysis (SRB, APB, IRB, etc.)
Findings are contextualized for your system, identification of dominant risk pathways
Treatment decisions are data-driven, not guessed
Follow-up expert consultation is built into the process

Case Study: The ROI of Biocide Selection Studies

See how data-driven testing can significantly reduce chemical spend while improving microbial control. This case study demonstrates how OSP’s biocide selection study identified a treatment strategy that reduced dosing frequency and lowered annual treatment costs.

Download Full Case Study

Frequently Asked Questions

Kill Study (Biocide Selection Study)

What is a kill study (biocide selection) study?

A kill study (biocide selection study) is a controlled laboratory evaluation designed to determine which biocide chemistry performs most effectively against the microbial population present in your specific system. Rather than relying on an inconsistent treatment program, a selection study tests multiple candidate biocides directly against the water source to measure real-world efficacy. The goal is to identify the chemistry and dosage that delivers the most reliable microbial control for your unique microbial community and
operating conditions.

Why is a kill study (biocide selection study) necessary?

Microbial communities vary significantly between water sources and applications. A biocide that performs well in one system may underperform in another due to
differences in microbial composition, biofilm presence, salinity, temperature, and chemical compatibility. A kill study eliminates guesswork by generating data-driven comparisons between treatment options.

How does ATP testing support a kill study (biocide selection study)?

ATP testing plays a central role in kill studies by providing a rapid, quantitative measurement of active microbial biomass before and after treatment. Because ATP reflects living microbial activity, it allows for precise evaluation of how effectively each candidate biocide reduces microbial load. By comparing ATP reductions
across different chemistries, dosages, and durations, OSP can determine which product achieves the greatest microbial kill under simulated field conditions. This rapid turnaround makes ATP an ideal tool for performance comparisons.

What information does a kill study (biocide selection study) provide?

A typical kill study provides baseline microbial activity, post-treatment microbial measurement, measurements taken after re-inoculation, and comparative performance across multiple biocide chemistries and concentrations. Results clearly demonstrate which product delivers the strongest and most consistent microbial reduction, typically reported as a “log reduction in bacteria”.

What types of biocides can be evaluated?

Kill studies can compare oxidizing and non-oxidizing chemistries, including glutaraldehyde blends, quaternary ammonium compounds, DBNPA, bronopol, isothiazolinones, etc. Studies can also assess combination treatments or dosing strategies to evaluate potential synergistic effects.

How long does a kill study (biocide selection study) take?

Because ATP testing provides results in minutes, bacterial measurements can often be generated on-site or in the lab, as soon as the sample is received. More detailed studies that include a comparison of several biocides across multiple dosages may extend over several days or weeks. The overall timeline depends on study design and project scope.

When should a kill study (biocide selection study) be conducted?

A kill study is recommended when an untested water source is being utilized, addressing persistent souring or corrosion, experiencing inconsistent biocide performance, evaluating cost reduction opportunities, or transitioning between chemistries. It is also valuable before scaling up treatment in high-value assets where failure risk is significant.

How does a kill study (biocide selection study) reduce operating costs?

By identifying the most effective chemistry and optimal dosage, selection studies prevent chronic overdosing and reduce wasted chemical spend. They also minimize the risk of asset damage caused by ineffective microbial control. Data-driven treatment optimization supports longer equipment life, fewer shutdowns, and more stable
production performance.

ATP Testing

Why is microbial monitoring important in oil and gas and industrial water systems?

Microbial activity in oilfield and industrial water systems can lead to significant operational challenges, including biogenic souring (hydrogen sulfide production), microbiologically influenced corrosion (MIC), iron sulfide scale formation, plugging, and biofilm development. Left unmanaged, these issues can result in equipment failure, production downtime, and increased operating costs. Effective microbial monitoring allows operators to identify risks early, implement targeted mitigation strategies, and optimize biocide treatment programs before damage escalates.

What is ATP testing?

ATP testing measures adenosine triphosphate (ATP), a molecule present in all living cells. By quantifying ATP in a sample, the test provides a rapid and quantitative estimate of total active microbial load. The 2nd gen ATP testing system is specifically designed for oil and gas-associated waters, including commingled and hydrocarbon-containing fluids, where 1 st gen ATP systems may struggle due to interferents.

What information does ATP testing provide?

ATP testing reports the mass of ATP present in the sample, which represents the total active and living microbial biomass. Since ATP degrades quickly once cells die, the method reflects real-time biological activity rather than historical contamination. It does not identify specific organisms but instead provides a quantitative measurement of overall microbial activity

Why is ATP testing suitable for oilfield waters?

Oilfield waters often contain interferents that can distort traditional ATP measurements. ATP testing incorporates a rinse reagent step to account for these interferents, improving accuracy and consistency in complex fluid systems.

When should ATP testing be used?

ATP testing is commonly used for routine microbial monitoring, trending microbial load over time (days/weeks/months), verifying biocide treatment performance, and supporting biocide selection studies. It provides a fast, practical tool for everyday asset management.

How do I send in water samples for ATP testing?

In the absence of OSP-provided sample preservation bottles, collect a representative water sample in a clean, airtight container with minimal headspace. Keep the sample cool (4–10°C), and ship to OSP within 24–48 hours of collection. Please follow our official Sampling Guidelines for container requirements, labeling, and shipping instructions to ensure accurate and reliable results.

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