A laboratory temperature and humidity acquisition and alarm system is designed based on wireless sensor networks（ WSNs） for the strict requirements of environmental conditions in the calibration laboratory. System uses STC12C5A60S2 microprocessor as controlcore to collect

process and store each sensor node data in the calibration laboratories

and realize remote transmission of data through GTM900 C module. When temperature and humidity exceed a set threshold

the system can automatically transmit the alarm message. System has high precision

strong practicability

stability and reliability

which can accurately monitor and record the temperature and humidity. System avoids the verification

calibration and test items in substandard conditions effectively

which has a strong practical application value.