0.01 PPM Resolution Compact, light weight, durable Battery status LED Short Term Averaging

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Environmental Sensor Co.’s Formaldehyde Meter is a hand held instrument that measures formaldehyde concentration with a range of 0-30 ppm and a resolution of 0.01 ppm. The instrument makes it possible to monitor formaldehyde vapor in air, for the purpose of indoor air quality testing. The instrument can be operated in either single point or continuous mode. In single point mode, the meter displays one highly accurate point of data. In continuous mode, the meter can be pre-set to operate for up to 90 minutes. Once the pre-set time period has elapsed, the meter calculates an average exposure value for the entire course of the measurement. Short measurement intervals are recommended for the greatest accuracy.

With the optional data-logging feature, the meter stores all of the exposure points for each use. The memory is dynamically managed, based on the length of operation, to maximize the capacity. The memory has the capacity to store data for up to 90 separate measurements or 13,500 points of data. A date and time stamp for each set of data is stored at the beginning of each use. All of the memory contents can be easily uploaded to PC using the terminal software included with the instrument or components available within Microsoft Windows.

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The Z-300 Formaldehyde Meter uses two filters to eliminate troublesome interferences. Measurements are first made with a filter that permits determination of the background or baseline. Insertion of a second filter then permits the measurement of formaldehyde. The instrument prompts the user for all required actions. The procedure is simple. The instrument will prompt the user to insert one filter, remove it, and insert another. With the use of the filter system, interferences are virtually completely removed. Only certain aldehydes and ketones need to be considered. The filters do not permit separations of these classes of compounds.

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The sensing element of the instrument is an electro-chemical cell. The cell is a four-electrode type, which contains a working and an active auxiliary electrode. The signal from the auxiliary electrode is used for temperature compensation and to improve the selectivity of the entire sensor. The sensor response is linear with the concentration of Formaldehyde in air.

Some representative examples of the common compounds and the corresponding response signals they give are shown below. Care needs to be exercised about using this instrument in the presence of large concentrations of interfering gases. Contact the manufacturer if difficulties are suspected with interfering gases, or with other usage problems. In addition variations in the baseline, as a result of variations in concentrations of compounds other than aldehydes or ketones, during the course of the measurement, can impact the reading.