HI-FLOW 2 – Meeting & Exceeding the High-Volume Sampler Demands of OOOOb

A high-volume sampler that complies with OOOOb and ACR methodologies

The Sensors Emissions Measurement Technology (SEMTECH) HI-FLOW 2 is a battery-powered, handheld high-volume sampler that uses cutting-edge flow and gas sensing technologies for the direct quantification of leaks in the 0.0005 to 25 CFM (0.015 to 700 lpm) range with accuracy within 5%.

However, just as important as highly accurate leak quantification, the HI-FLOW 2 also meets the demands of the EPA’s OOOOb.

OOOOb demands

Leak detection (range)

OOOOb states that flow measurement devices must “have a measurement range over the entire expected range of flow rates sampled.” Additionally, these devices are required to have a measurement range over “the entire expected range of concentrations.”

The HI-FLOW 2 offers a best-in-class dynamic range of 0.0005 to 25 CFM. This is a very large dynamic range that encompasses the expected range of sampled flow rates and concentrations.

Compliance

OOOOb demands that the gas concentrations and flow rates are accurately within 5%. The HI-FLOW 2 is manufactured to meet a higher accuracy of 2.5% for both components. Additionally, OOOOb requires:

• 3 separate 1-minute measurements are collected to determine a leak’s average leak rate. The difference between these samples must be less than 10%
• Methane gaseous calibration cylinder standards are used to challenge each sensor prior to and at the end of a testing day
• The cylinder value and a sensor reading must be less than 5% in difference of the respective calibration gas value at each point
• If the check fails at either point, the data from all tests performed prior to the previous passing calibration check must be invalidated

The HI-FLOW 2 comes with web-based software that generates reports in full compliance with OOOOb. All metrics associated with sensor testing, measurements, and leak detection are collected and formatted for appropriate report submission.

Regarding field testing, the HI-FLOW 2 has easily demonstrated compliance to the requirement that the relative difference between the three 1-minute measurements is less than 10%. And the HI-FLOW 2’s in-unit software delivers linearity performance validation and compliance information.

Design criteria for gas concentration measurement

According to OOOOb: “The methane sensor(s) must be selective to methane with minimal interference, less than 2.5 percent for the sum of responses to other compounds in the gas matrix. You must document the minimal interference though empirical testing or through data provided by the manufacturer of the sensor.” Moreover, the sensors must be linear and capable of meeting a maximum 5% accuracy criteria.

The HI-FLOW 2 meets NIST traceable certification to <2.5%:

Annual calibration requirements

OOOOb requires that flow measurement sensors are calibrated annually. As shown in Sensors, Inc.’s calibration certificates, the HI-FLOW 2 is calibrated annually:

Methane Analyzer Linearity Results