A continuous monitoring of critical environmental parameters to detect threshold or dosage violations is of strong interest throughout the life cycle of goods. The task is challenging, when there is no continuous supply of electric energy available and lowest cost sensor solutions are required - two common application constraints in wireless passive sensor applications, i.e., sensor enhanced RFID tags. Presented is an inkjet printed humidity threshold violation sensor, providing a permanent and pronounced electric resistance change due to a humidity exposure above a critical threshold. Exploited natural phenomena are the deliquescence of salts as humidity threshold detection mechanism, as well as chemical sintering of silver metal nano particles, in order to realize an irreversible state change. In difference to existing solutions based on spatially separated nanoparticle and salt reservoirs, it is possible to use an intermixed salt and nanoparticle region, in which a partially developed conductive percolation network exists after manufacturing.