Our Oven Heating System (OHS), commercialized as BONDS by IQOS, heats the tobacco using a blade-free resistive heating technology. Because the tobacco is heated and not burned with OHS, the levels of harmful chemicals in the generated aerosol are significantly reduced compared with cigarette smoke. Find out more about how this system works.
The OHS uses a blade-free heating technology, known as the ROUNDHEAT TOBACCO SYSTEM™, to heat tobacco without burning. The OHS operates by using external resistive heating technology to heat specially-designed heated tobacco units (HTUs), commercialized as BLENDS. The resistive technology heats the tobacco sticks from the outside and ensures precise and controlled heating.
The OHS is designed using the principle of heat-not-burn technology. It is made up of four major components:
The external resistive heater is composed of flexible polyimide stainless-steel tracks wrapped around a stainless-steel tube.
The temperature is monitored using the Temperature Coefficient of Resistance (TCR), which measures the change in electrical resistance of the heater tracks. The TCR control system transfers energy from the battery to the heater based on its resistance, reflecting the heater's average temperature. Control electronics ensure the chamber does not heat the tobacco beyond the maximum target temperature, maintaining the heater at the defined temperature and preventing overheating.
Additionally, the control electronics manage battery charging and the user interface. The battery provides enough power for three consecutive experiences and up to 25 experiences per charge.
The entire heating system is surrounded in a heat-shrink tube, which provides insulation and robustness.
The OHS is used with an HTU, which is designed to heat the tobacco without combustion, delivering a smoke-free experience. It includes:
The HTU is inserted from the top of the device into the stainless-steel tube inside the heating chamber, which is protected by a sliding cap. The design ensures that the resistive heater is positioned around the tobacco plug of the HTU. When the OHS is turned on, the tobacco is heated from the outside by the resistive heater, creating a nicotine-containing aerosol.
When the user takes a puff from the mouthpiece, air enters from the top at the inlet on the device and then flows in a “U” shape through the heating chamber. This way, the air is conveyed through the front plug of the HTU.
This airflow enables the evaporation of water, glycerin, and other components in the heated tobacco plug, which are then mixed with air entering the inner chamber of the cardboard tube through the ventilation holes. This promotes a temperature drop when a puff is taken, enhancing aerosol formation through the rapid cooling.
The aerosol generated by the OHS contains on average 95% lower levels of harmful and potentially harmful constituents (HPHCs), compared with cigarettes. However, this does not necessarily equal a 95% reduction in risk. The OHS is not risk free and contains nicotine, which is addictive. But for adult smokers who don’t quit, it is a better alternative than continued smoking.
For communicating the extent of HPHCs emitted by our smoke-free products, we use reduced emission statements, which indicate the relative reductions of a selected number of toxicants in the emissions of smoke-free products compared with cigarettes.
The approach used by PMI to substantiate reduced emissions for consumer-facing product statement is based on the World Health Organization (WHO) 9 list. This is a list of nine priority HPHCs proposed by the WHO Study Group on Tobacco Product Regulation for mandated lowering in cigarette smoke, which does not include nicotine.
PMI selected the WHO 9 because it allows us to provide consumers with accurate and nonmisleading information while improving the consistency of the messages across product categories and aligning with industry practices. Furthermore, this approach enables consumers to make informed decisions about the products available on the market, including product properties, benefits, and risks.
Explore the 30 years of innovation behind our heated tobacco products. Read key information on each iteration, and learn how the user experience, heating technology, and battery technology have evolved over time.
