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tokens: polarized emission in the OMC-1 region was obtained as part of the BISTRO large program (project code M16BL004; Ward-Thompson et al. 2017 ) and the POL-2 commissioning project (project code M15BEC02, Friberg et al. 2016 , 2018 ; P. Bastien et al. 2021, in preparation). In the BISTRO program, the OMC-1 region was observed 21 times between 2016 January 11 and 24, in Band 1 or Band 2 weather conditions, τ 225 GHz 0.05 or 0.05 ≤ τ 225 GHz 0.08, where τ 225 GHz is the atmospheric opacity at 225 GHz. The total on-source time is 14 hr. These data were first published by Ward-Thompson et al. ( 2017 ). We excluded one of these data sets because the observation was incomplete. A further set of 15 observations of the OMC-1 region was made between 2017 December 8 and 2018 January 10, as part of the POL-2 450 μ m commissioning campaign. As part of the effort to characterize the instrumental polarization at 450 μ m, these observations were made without the JCMT Gore Tex in place. Most of these observations were obtained in Band 1 weather condition ( τ 225 GHz 0.05) with a total on-source time of 7.9 hr. We publish these observations of the commissioning campaign and the polarization data of the two projects at 450 μ m for the first time. A total of 35 data sets at 450 and 850 μ m from these two projects were used in this paper. We combined all 35 data sets of the OMC-1 region and reduced them using the pol2map routine in the Sub-Millimetre User Reduction Facility (SMURF) package of the Starlink software (Jenness et al. 2013 ) with the latest Instrumental Polarization (IP) model, “2019 August.” 41 41 https://www.eaobservatory.org/jcmt/2019/08/new-ip-models-for-pol2-data/ There are three main stages of the POL-2 data reduction process. Polarized light is represented by the Stokes parameters, I , Q , and U . First, the raw time-series data are converted into Stokes I , Q , and U time streams using the calcqu command. Then, the makemap routine is used to make an initial reference Stokes I map from each data set, gridded onto 4′′ pixels. A coadded total intensity map is created from all of these initial Stokes I maps. Next, pol2map generates two “masks,” named ASTMASK and PCAMASK, from the coadded total intensity map. The ASTMASK is a fixed signal-to-noise-based mask, which is used to define regions of astrophysical emission in the coadded total intensity map. The PCAMASK defines source regions in order to exclude the regions containing emission when making a background model with makemap . See Mairs et al. ( 2015 ) for a detailed discussion of the role of masking in SCUBA-2 data reduction. pol2map makes an improved Stokes I map of each data set by using these fixed masks, increasing the number of principal component analysis (PCA) components over the first reduction, and using the skyloop implementation of makemap , wherein each iteration of the mapmaker is performed on each of the observations in turn, rather than each observation being reduced consecutively.