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<p>We present the laboratory results of immersion freezing efficiencies of cellulose particles at supercooled temperature (<span class="inline-formula"><i>T</i>)</span> conditions. Three types of chemically homogeneous cellulose samples are used as surrogates that represent supermicron and submicron ice-nucleating plant structural polymers. These samples include microcrystalline cellulose (MCC), fibrous cellulose (FC) and nanocrystalline cellulose (NCC). Our immersion freezing dataset includes data from various ice nucleation measurement techniques available at 17 different institutions, including nine dry dispersion and 11 aqueous suspension techniques. With a total of 20 methods, we performed systematic accuracy and precision analysis of measurements from all 20 measurement techniques by evaluating <span class="inline-formula"><i>T</i></span>-binned (1&thinsp;<span class="inline-formula">^∘</span>C) data over a wide <span class="inline-formula"><i>T</i></span> range (<span class="inline-formula">−</span>36&thinsp;<span class="inline-formula">^∘</span>C&thinsp;<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>&lt;</mo><mi>T</mi><mo>&lt;</mo><mo>-</mo><mn mathvariant="normal">4</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="46pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="3b7a6b6ea4e55ac45ae2885dad986a21"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-19-4823-2019-ie00001.svg" width="46pt" height="10pt" src="acp-19-4823-2019-ie00001.png"/></svg:svg></span></span>&thinsp;<span class="inline-formula">^∘</span>C). Specifically, we intercompared the geometric surface area-based ice nucleation active surface site (INAS) density data derived from our measurements as a function of <span class="inline-formula"><i>T</i></span>, <span class="inline-formula"><i>n</i>_s,geo(<i>T</i>)</span>. Additionally, we also compared the <span class="inline-formula"><i>n</i>_s,geo(<i>T</i>)</span> values and the freezing spectral slope parameter (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M12" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><mi mathvariant="normal">log</mi><mo>(</mo><msub><mi>n</mi><mrow><mi mathvariant="normal">s</mi><mo>,</mo><mi mathvariant="normal">geo</mi></mrow></msub><mo>)</mo><mo>/</mo><mi mathvariant="normal">Δ</mi><mi>T</mi><mo>)</mo></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="83pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="8ec71e136abcca72f65a4b88c200015b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-19-4823-2019-ie00002.svg" width="83pt" height="16pt" src="acp-19-4823-2019-ie00002.png"/></svg:svg></span></span> from our measurements to previous literature results. Results show all three cellulose materials are reasonably ice active. The freezing efficiencies of NCC samples agree reasonably well, whereas the diversity for the other two samples spans <span class="inline-formula">≈</span>&thinsp;10&thinsp;<span class="inline-formula">^∘</span>C. Despite given uncertainties within each instrument technique, the overall trend of the <span class="inline-formula"><i>n</i>_s,geo(<i>T</i>)</span> spectrum traced by the <span class="inline-formula"><i>T</i></span>-binned average of measurements suggests that predominantly supermicron-sized cellulose particles (MCC and FC) generally act as more efficient ice-nucleating particles (INPs) than NCC with about 1 order of magnitude higher <span class="inline-formula"><i>n</i>_s,geo(<i>T</i>)</span>.</p>