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

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Environmental Sensor Co.뭩 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, while performing operations using Formaldehyde solution or obtain a single, highly accurate point for the purpose of indoor air quality testing. The instrument can be operated in either single point or continous mode. In single point mode, the meter displays measurement of formaldehyde in air. In continous mode, the meter can be pre-set to operate for up to 90 minutes. When the pre-set time period has elapsed, the meter calculates an average exposure value for the entire course of the measurement.

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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.

PERFORMANCE DATA
Sensor Nominal Range Maximum PPM Resolution Warm-Up Time (Normal Conditions) Sensor Response Time (90% peak) Repeatability Zero Drift Sensitivity Loss Operating Temperature Pressure Range Relative Humidity Dimensions Weight Power Source Battery Life Sensor Life	Electrochemical 0-30 ppm 34 ppm 0.01 ppm 3 minutes <60 Seconds 1% of signal <0.002 ppm per min. <5%/year 0-40캜 Atmospheric ?10% 15 to 90% non-condensing HxDxW 4.75"x2.5"x1.5" 170 gms 9-V Alkaline Battery 240 hours 2+ years

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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 (about three minutes), can impact the reading.

CROSS SENSITIVITY DATA
Gas	Sensor Interference's Percent of Formaldehyde PPM	Interference's After Use of Filters
Acetone Methylethyl Ketone Diethyl Ketone Acetaldehyde Acetic Acid Ethylene Methanol Ethanol i-propanol Carbon Monoxide	2 2 2 12 0 67 125 55 44 40	2 2 2 0 0 0 0 0 0 0