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<p>Proton-transfer-reaction mass spectrometry (PTR-MS) is widely used in atmospheric sciences for measuring volatile organic compounds in real time. In the most widely used type of PTR-MS instruments, air is directly introduced into a chemical ionization reactor via an inlet capillary system. The reactor has a volumetric exchange time of <span class="inline-formula">∼0.1</span> s, enabling PTR-MS analyzers to measure at a frequency of 10 Hz. The time response does, however, deteriorate if low-volatility analytes interact with surfaces in the inlet or in the instrument. Herein, we present the extended volatility range (EVR) PTR-MS instrument which mitigates this issue. In the EVR configuration, inlet capillaries are made of passivated stainless steel, and all wetted metal parts in the chemical ionization reactor are surface-passivated with a functionalized hydrogenated amorphous silicon coating. Heating the entire setup (up to 120 <span class="inline-formula">^∘</span>C) further improves the time-response performance.</p> <p>We carried out time-response performance tests on a set of 29 analytes having saturation mass concentrations <span class="inline-formula"><i>C</i>⁰</span> in the range between <span class="inline-formula">10⁻³</span> and <span class="inline-formula">10⁵</span> <span class="inline-formula">µg m⁻³</span>. The <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">1</mn><mo>/</mo><mi>e</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="21pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="82e0823fe03ff0dee1c3117688ee2eff"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-1355-2021-ie00001.svg" width="21pt" height="14pt" src="amt-14-1355-2021-ie00001.png"/></svg:svg></span></span>-signal decay times after instant removal of the analyte from the sampling flow were between 0.2 and 90 s for gaseous analytes. We also tested the EVR PTR-MS instrument in combination with the chemical analysis of aerosols online (CHARON) particle inlet, and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">1</mn><mo>/</mo><mi>e</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="21pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="416b5cf6c9c03be8e7b25ad586ee718a"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-14-1355-2021-ie00002.svg" width="21pt" height="14pt" src="amt-14-1355-2021-ie00002.png"/></svg:svg></span></span>-signal decay times were in the range between 5 and 35 s for particulate analytes. We show on a set of example compounds that the time-response performance of the EVR PTR-MS instrument is comparable to that of the fastest flow tube chemical ionization mass spectrometers that are currently in use. The fast time response can be used for rapid (<span class="inline-formula">∼1</span> min equilibration time) switching between gas and particle measurements. The CHARON EVR PTR-MS instrument can thus be used for real-time monitoring of both gaseous and particulate organics in the atmosphere. Finally, we show that the CHARON EVR PTR-MS instrument also rapidly detects highly oxygenated species (with up to eight oxygen atoms) in particles formed by limonene ozonolysis.</p>