Environmental Sensors Co.`s Formaldehyde Meter is a portable desktop instrument that measures formaldehyde concentration in a range of 0-30 ppm and a resolution of 0.01ppm. The instrument makes it possible to monitor formaldehyde vapor in air. The insturment has an LCD display giving concentrations in ppm every 10 seconds, a low battery indicator, and an audible alarm that can be set at any level from 0-30 ppm. With the touch of a button, the meter displays STEL (average of every 15 min.), TWA (8 hour average) and Peak. The internal pump makes it possible to sample from hard-to-reach areas or confined spaces by attaching a flexible tube to the meter.