CS1200E Passive Canister Sampler - Solutions for Time Integrated Canister Sampling

Importance of the Topic

Time‐integrated canister sampling of VOCs provides accurate, low‐level measurement of atmospheric and indoor air contaminants without continuous power or active pumping. Reliable recovery of EPA TO‐14 and TO‐15 target compounds at sub‐ppb levels is essential for environmental monitoring, compliance testing, and industrial air quality control.

Study Objectives and Overview

This application note describes the design, performance, and advantages of the CS1200E passive canister sampler. Key goals include demonstrating stable, reproducible flow control over durations from minutes to one month, validating compound recovery, and highlighting system inertness and field usability.

Methodology

A mechanical, high‐purity flow regulator uses sapphire critical orifices and spring‐loaded pressure regulation to draw canister vacuum from initial negative pressure to within 1 psi of ambient at a constant rate. Multiple orifices cover flow ranges from 0.1 to 450 cc/min, enabling fill times from 15 minutes up to 30 days. The system operates tool‐free, requires no external power, and resists flow variations across −20 °C to +50 °C.

Used Instrumentation

• CS1200E Passive Canister Sampler with Silonite™ coating
• Sapphire critical orifices (nine flow-range options)
• Electropolished and Silonite™-coated inlet lines
• Silonite™-coated stainless steel inlet filter
• High‐resolution vacuum gauge with 1/4″ compression fitting

Main Findings and Discussion

• The CS1200E achieved constant flow fill of 6 L canisters for up to 30 days with less than 1 % flow drift.
• Silonite™ surface treatment and electropolishing minimize adsorption of polar and heavier VOCs, improving compound recovery compared to untreated stainless steel.
• Field rain‐guard inlet cap and filter prevent moisture and particulate contamination during sampling.
• Stability tests across ambient temperatures confirm consistent performance where comparable frit or needle‐valve controllers show greater variability.

Benefits and Practical Applications

• Passive operation eliminates power supplies and simplifies field deployment.
• Wide dynamic range of integration times supports short‐term leaks to long‐term background monitoring.
• High chemical inertness yields quantitative analysis for C1–C12 VOCs at sub‐ppb detection limits.
• Modular design with interchangeable orifices allows rapid configuration changes on site.

Future Trends and Potential Uses

Advances in surface coatings and microfabricated orifice technology may further reduce adsorption and extend flow stability. Integration with wireless pressure logging and automated calibration services will streamline data capture and quality assurance. Coupling passive samplers with robotic deployment in remote or harsh environments has potential for large‐scale, unattended monitoring networks.

Conclusion

The CS1200E passive canister sampler offers a robust, inert, and highly stable solution for time‐integrated VOC sampling in environmental and industrial applications. Its power‐free operation, broad flow range, and proven compound recovery make it an industry benchmark for EPA TO‐15 monitoring.

Reference

• Entech Instruments CS1200E Passive Canister Sampler Application Note, 2019.