As with any new product, your Molekule Air purifier is exposed to dust and other contaminants during the warehousing and shipping of the device. Please run the unit for 24-48 hours to break down any contaminants that may have settled on the PECO-Filter, thus allowing for it to reach full efficacy. You may notice a smell during this initial period; however, running the device will break down any compounds picked up in shipping and the smell should be reduced after continued use.