[{"data":1,"prerenderedAt":392},["ShallowReactive",2],{"doc-\u002Fverticals\u002Fclimate":3},{"id":4,"title":5,"body":6,"description":382,"edit":383,"extension":384,"meta":385,"navigation":386,"path":387,"seo":388,"stem":389,"vertical":59,"weight":390,"__hash__":391},"content\u002Fverticals\u002Fclimate.md","Indoor climate",{"type":7,"value":8,"toc":371},"minimark",[9,13,29,34,37,43,53,69,75,84,88,96,99,185,196,201,205,208,284,287,291,294,310,314,317,337,341],[10,11,12],"p",{},"Indoor air monitoring covers four sub-cases that share infrastructure\n(CO₂ NDIR sensor + T\u002FRH probe) but have wildly different thresholds:",[14,15,16,20,23,26],"ol",{},[17,18,19],"li",{},"Schools and offices — CO₂ as a ventilation proxy.",[17,21,22],{},"Museums and instrument storage — RH stability.",[17,24,25],{},"Wine cellars — both, on long time-scales.",[17,27,28],{},"Indoor cannabis \u002F greenhouses (not regulated, included because we\nget the question).",[30,31,33],"h2",{"id":32},"schools-and-offices-co","Schools and offices — CO₂",[10,35,36],{},"CO₂ levels in occupied rooms are the simplest proxy for ventilation\nadequacy. Outdoor air is ~420 ppm in 2026; comfortable indoor air is\n\u003C 1000 ppm; > 1400 ppm causes measurable cognitive impairment;",[38,39,40],"blockquote",{},[10,41,42],{},"2000 ppm is a sign the room is functionally unventilated.",[44,45,50],"reg",{"code":46,"jurisdiction":47,"source":48,"title":49},"REHVA \u002F WHO","non-binding guidance, EU","https:\u002F\u002Fwww.rehva.eu","CO₂ guidance for schools and offices",[10,51,52],{},"REHVA (the European HVAC association) recommends ≤ 800 ppm as a design\ntarget, ≤ 1000 ppm as a practical operating ceiling, and ≤ 1400 ppm as\nthe threshold above which Category IV ventilation is considered failed.\nSlovak ŠENV school operating regulations follow these thresholds in\nspirit.",[10,54,55,56,60,61,64,65,68],{},"OpenSense defaults for a ",[57,58,59],"code",{},"climate"," site labelled ",[57,62,63],{},"school"," or ",[57,66,67],{},"office",":",[70,71],"stoplight",{"alarm":72,"ok":73,"warn":74},"> 1400 ppm sustained 15 min — open windows or call HVAC","\u003C 1000 ppm","1000–1400 ppm sustained 15 min",[10,76,77,78,83],{},"Recommended sensor: Sensirion SCD41 NDIR-based CO₂ + T\u002FRH on an ESP32\n(see ",[79,80,82],"a",{"href":81},"\u002Fhardware\u002Fdiy-esp32","DIY ESP32","). Commercial alternatives:\nAranet4 (BLE, needs a gateway), Airthings (proprietary cloud,\ncontact us).",[30,85,87],{"id":86},"museums-relative-humidity-stability","Museums — relative humidity stability",[10,89,90,91,95],{},"For museum collections and musical instruments, the ",[92,93,94],"strong",{},"rate of change","\nof RH matters more than the absolute value. Pianos, wooden furniture,\nparchment and oil paintings all warp at different rates when humidity\nswings.",[10,97,98],{},"Standard targets (Bizot Group \u002F Smithsonian \u002F V&A guidance):",[100,101,102,118],"table",{},[103,104,105],"thead",{},[106,107,108,112,115],"tr",{},[109,110,111],"th",{},"Object class",[109,113,114],{},"Target RH",[109,116,117],{},"Drift tolerance",[119,120,121,133,143,153,163,174],"tbody",{},[106,122,123,127,130],{},[124,125,126],"td",{},"Oil on canvas",[124,128,129],{},"45–55 %",[124,131,132],{},"± 5 % per month",[106,134,135,138,140],{},[124,136,137],{},"Wooden furniture",[124,139,129],{},[124,141,142],{},"± 7 % per month",[106,144,145,148,151],{},[124,146,147],{},"Paper, parchment, books",[124,149,150],{},"30–50 %",[124,152,132],{},[106,154,155,158,161],{},[124,156,157],{},"Photographs (acetate)",[124,159,160],{},"30–40 %",[124,162,132],{},[106,164,165,168,171],{},[124,166,167],{},"Musical instruments (wood)",[124,169,170],{},"40–55 %",[124,172,173],{},"± 3 % per week",[106,175,176,179,182],{},[124,177,178],{},"Iron \u002F steel artefacts",[124,180,181],{},"\u003C 40 %",[124,183,184],{},"dryer is better",[10,186,187,188,191,192,195],{},"OpenSense supports a ",[57,189,190],{},"derived_drift"," channel: ",[57,193,194],{},"max(|RH_now − RH_avg_7d|)",".\nAlarms fire when the drift exceeds the configured tolerance, not when\nthe absolute reading is out of range. This is the inverted view museums\ncare about.",[70,197],{"alarm":198,"ok":199,"warn":200},"Drift > 2× tolerance — climate system is broken","Drift \u003C tolerance \u002F 2","Drift > tolerance",[30,202,204],{"id":203},"wine-cellars","Wine cellars",[10,206,207],{},"Industry consensus for table-wine cellaring:",[100,209,210,226],{},[103,211,212],{},[106,213,214,217,220,223],{},[109,215,216],{},"Variable",[109,218,219],{},"Target",[109,221,222],{},"Acceptable",[109,224,225],{},"Why",[119,227,228,242,256,270],{},[106,229,230,233,236,239],{},[124,231,232],{},"Temperature",[124,234,235],{},"12 °C",[124,237,238],{},"10–15 °C",[124,240,241],{},"Slow, even ageing",[106,243,244,247,250,253],{},[124,245,246],{},"RH",[124,248,249],{},"70 %",[124,251,252],{},"60–80 %",[124,254,255],{},"Cork stays sealed; labels survive",[106,257,258,261,264,267],{},[124,259,260],{},"Temp swing",[124,262,263],{},"\u003C 2 °C \u002F week",[124,265,266],{},"\u003C 5 °C \u002F week",[124,268,269],{},"Cork breathes, oxygen ingress",[106,271,272,275,278,281],{},[124,273,274],{},"Light",[124,276,277],{},"dark",[124,279,280],{},"dim, no UV",[124,282,283],{},"(Not measured by OpenSense yet)",[10,285,286],{},"For investment-grade cellaring the constraints tighten by ~30 %; the\ndefaults above are the operational compromise that lets you store cases\nwithout sleeve-by-sleeve obsession.",[30,288,290],{"id":289},"greenhouse-grow-room","Greenhouse \u002F grow-room",[10,292,293],{},"Not regulated. Pure ops:",[295,296,297,300,303],"ul",{},[17,298,299],{},"CO₂ enriched to 800–1200 ppm during photoperiod for accelerated growth.",[17,301,302],{},"RH 50–70 % vegetative, 40–55 % flowering.",[17,304,305,306,309],{},"VPD (vapour pressure deficit) is the modern variable; OpenSense derives\nVPD from T + RH if you flag a channel as ",[57,307,308],{},"grow_room",".",[30,311,313],{"id":312},"a-note-on-indoor-air-quality-beyond-co","A note on indoor air quality beyond CO₂",[10,315,316],{},"We deliberately do not currently support:",[295,318,319,325,331],{},[17,320,321,324],{},[92,322,323],{},"PM 2.5 \u002F PM 10",": there are cheap sensors (Plantower PMS5003 etc.)\nbut the public-health interpretation is tricky and varies by\njurisdiction. We will add it once we ship a calibration story.",[17,326,327,330],{},[92,328,329],{},"VOC",": SGP30\u002FSGP40 sensors are noisy; the calibration drift is too\nhigh to alarm on. We can ingest the channel but do not run rules on it.",[17,332,333,336],{},[92,334,335],{},"Radon",": long-term integration, weeks of measurement, not real-time.\nDifferent product category.",[30,338,340],{"id":339},"sources","Sources",[295,342,343,350,357,364],{},[17,344,345],{},[79,346,349],{"href":48,"rel":347},[348],"nofollow","REHVA — Federation of European HVAC associations",[17,351,352],{},[79,353,356],{"href":354,"rel":355},"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FBizot_Group",[348],"Bizot Group — Green Protocol on environmental standards for museum loans",[17,358,359],{},[79,360,363],{"href":361,"rel":362},"https:\u002F\u002Fwww.si.edu",[348],"Smithsonian — Museum environment guidelines",[17,365,366],{},[79,367,370],{"href":368,"rel":369},"https:\u002F\u002Fwww.ashrae.org",[348],"ASHRAE Handbook — Applications, Chapter 24: Museums, Galleries, Archives",{"title":372,"searchDepth":373,"depth":373,"links":374},"",3,[375,377,378,379,380,381],{"id":32,"depth":376,"text":33},2,{"id":86,"depth":376,"text":87},{"id":203,"depth":376,"text":204},{"id":289,"depth":376,"text":290},{"id":312,"depth":376,"text":313},{"id":339,"depth":376,"text":340},"CO₂, RH for schools, offices, museums, wine cellars",null,"md",{},true,"\u002Fverticals\u002Fclimate",{"title":5,"description":382},"verticals\u002Fclimate",340,"UtCdbXftZK_OeYKc2DLgqjA8pnUKo000iwroKG8jeAs",1779022955039]