Advantages of Permeation Devices

Advantages of Permeation Devices

Disadvantages of Bottled Standards

• Use of a pure substance in an inert matrix
• Precise concentrations of gases
• Rapid availability and ease of handling
• Multi-component gas mixtures are easily generated with NIST traceability using established EPA and ASTM protocols
• Simple to remove and/or add a single component
• Wide range of concentrations easily generated by varying the dilution flow rate and/or the setpoint temperature
• Obtain difficult-to-source chemicals in desired quantities
• No dangerous goods shipping or reporting required
• No oven or Dynacalibrator® required
• Minimal lab space required

• Expensive due to rental fees and high disposal costs
• Substances are balanced in another medium
• Large number of gas cylinders needed for calibrations requiring multiple components over a wide range of concentrations
• Cylinders and equipment consume valuable lab space
• Possible degradation of standard within the cylinder:
• Changes in concentration levels due to changes in cylinder pressure
• Interaction of calibration components and surfaces
• Mutually reactive chemicals cannot be used
• Permitting may be required for some chemicals
• Specialized dangerous goods handling procedures may be required