Monitoring dangerous aerosols in indoor environments is essential to prevent illnesses and to provide safety to inhabitants. Natural gas in particular is an explosive chemical widely adopted in homes. Failures in its distribution network can be very harmful. We propose a WGSN to monitor indoor environments and to promptly report alarms in case of failures and leakages. It employs low-cost off-the-shelf devices like chemoresistive MOX sensors and state-of-the-art wireless electronic boards. We exploited the transient response of the sensing element to reduce by 20× the power required to assess the indoor air quality. Performance evaluation has been conducted using gas bench and demonstrates the effectiveness of our approach. Our system requires very few mW of power to work and enhances the battery autonomy of about 300\% with respect to nominal use of the sensor, with two standard AA batteries.