Accurately Monitoring Worker Exposure to Hazardous Substances

Industrial HygieneAccording to the Occupational Safety and Health Administration (OSHA), “Industrial hygienists use environmental monitoring and analytical methods to detect the extent of worker exposure and employ engineering, work practice controls, and other methods to control potential health hazards.” During a worksite analysis, industrial hygienists will employ air sampling methods and instruments to check the air for particulate and gas contaminants, dusts, fumes, mists, and aerosols.

An accurate flow rate during air sampling is an important factor in getting accurate exposure data. Regulatory bodies like OSHA recommend flow calibration as a standard step in the air sampling process. Industrial hygienists will commonly perform air flow calibrations before and after the sampling period.

Accuracy counts. When it comes to protecting people’s health and their lives, it really counts.


New OSHA respirable Crystalline Silica Rule

A Partnership in Air Measurement Quality

To ensure that your air sampling measurements are defensible, you need an air flow calibrator that is highly accurate, durable, and easy-to-use. Our Defender series flow calibrators offer a 1% volumetric accuracy and will begin measuring flow with the push of a button. This means that workers can ensure their sampling pump flow accuracy quickly and with very little training.

We understand that flexibility is crucial to your processes.

That’s why The Defender makes it easy to switch between units of measure and sampling modes. If you wish to measure standardized flow, we offer one model that will measure both volumetric and standardized accuracy, and two that measure gas temperature & pressure. To save time recording your measurements, you can connect your Defender up to a computer running the free DryCal Pro software and it will automatically log and plot your flow measurements while you sample.

Our DryCal calibrators are manufactured and serviced in Mesa Labs ISO-17025 certified and NVLAP accredited facility.

Regulatory agencies place strict requirements on the accuracy and traceability of your flow calibrators. Each new calibrator comes with a certificate demonstrating full NIST traceability. We recommend an annual recertification to ensure that your calibrator is ensure your flow data is defensible. Recertification services at our facility include full refurbishment, repair, and recertification demonstrated by the NIST-traceable certificate. All manufacturing and recertification is performed in Mesa Labs ISO-17025-certified and NVLAP accredited laboratory

What You Can Calibrate

  • Sampling Pumps
  • Particle Monitors
  • Gas Analyzers
  • Rotameters
  • Mass Flow Meters & Controllers

Worker Air Quality (web)

Numerous industries must conduct worker exposure airborne assessments according to OSHA regulations.

OSHA has the right to inspect any workplace suspected of violating their standards. These industries include: construction, agriculture, maritime, mining, oil and gas, metalworking, and many others. OSHA publishes guidelines and methodologies on how the workplace assessments are to be conducted, including a technical manual with instructions on how air sampling needs to be conducted. OSHA advises calibrating personal sampling pumps before and after each sampling period.

OSHA publishes guidelines and methodologies on how the workplace assessments are to be conducted, including a technical manual with instructions on how air sampling needs to be conducted.

As techniques trusted by OSHA and MHSA, our solutions are promised to meet the equipment requirements under these regulations.

Regulatory Compliance

Mine Safety and Health Administration (MSHA)

  • Per the Mine Safety and Health Administration (MSHA) Metal/Non-Metal Mine Health Inspection Procedures, Chapter 4, “The airflow calibrator unit must fall within tolerance of the reference volume measured by a master calibration standard. Each unit must fall within +1% of the reference volume measured with the certified (NIST traceable) laboratory/factory calibrated master unit.” We are proud to be specifically highlighted in their methods. The Defender meets this requirement by providing a certificate that shows 1% volumetric accuracy directly traceable to NIST.

Occupational Safety and Health Administration (OSHA)

The National Institute for Occupational Safety and Health (NIOSH)

Defender Series

Flow Ranges: Low (5-500ccm), Medium (50-5,000ccm), High (300-30,000ccm)
Accuracy Volumetric (% of reading): +/- 1%
Volumetric Flow Readings: mL/min, L/min, cc/min, cf/min


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We provide a wide range of flow rates and particle size cut points to help you meet even the strictest regulatory standards.


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