{ "articles": [ { "canonicalRoute": "/science/heat-balance/", "description": "Follow heat entering, accumulating in and leaving a building before treating a hot-space complaint as an equipment-size decision.", "eyebrow": "Building science \u00b7 Energy balance", "lede": "A hot room is the visible result of competing heat rates. The useful question is not only whether cooling equipment is running, but whether the whole building is gaining heat faster than heat is being removed from the occupied zone.", "limitations": [ "This workflow does not replace an engineered cooling-load calculation or equipment-selection procedure.", "Infrared images show apparent surface-temperature patterns; they do not measure heat flow or identify a cause by themselves.", "A cold supply-air reading does not establish delivered airflow, total capacity or occupied-zone heat removal.", "Weather, thermal storage, occupancy and control changes can make non-simultaneous comparisons misleading." ], "measurements": [ "GCT field method 1 \u2014 Define the complaint condition: record the zone, date, local time, desired outcome, occupancy and repeating event that makes the problem observable.", "GCT field method 2 \u2014 Record boundary conditions: measure indoor and outdoor dry-bulb temperature in \u00b0C (\u00b0F optional), record outdoor dew point, sun exposure, door activity and material changes in weather or use; identify sensor, location and stabilization time.", "GCT field method 3 \u2014 Map gains and pathways: inventory major envelope, outdoor-air and internal gains, and mark each as observed, estimated or unknown. Do not assign a heat rate without supporting input data and method.", "GCT field method 4 \u2014 Record system delivery during the same window: equipment mode, runtime, staging, setpoints, supply and return conditions, airflow evidence and heat-rejection state. A temperature difference without validated airflow is not a total-capacity measurement.", "GCT field method 5 \u2014 When authorized, change one bounded variable, preserve the baseline and repeat the observations long enough to see the response. Report no change and inconclusive results as faithfully as improvement." ], "mechanism": [ "Literature summary: heat balance accounts for rates of energy transfer. If solar gain, conduction, outdoor-air exchange, people, lighting and equipment together add heat faster than the cooling system removes it, zone temperature rises. When the rates approach balance, temperature may stabilize even though the space remains above the desired condition.", "The envelope, glass, roof, doors and ventilation connect indoor conditions to weather. Internal gains can change just as sharply: occupied kitchens, process equipment, lighting and electronics can shift the balance without a mechanical failure. Report heat rates in watts or kilowatts; installed U.S. equipment may also show Btu/h, where 1 kW is approximately 3412 Btu/h.", "Nominal refrigeration capacity is not identical to heat removed from each occupied zone. Airflow, return paths, duct leakage, controls, coil condition and heat rejection determine how much useful cooling reaches the complaint area under the observed condition.", "Buildings store heat in air, contents and assemblies, so timing matters. A short snapshot may miss solar lag, occupancy peaks, control staging or recovery after shutdown. A defensible investigation ties observations to time, weather, use and operating state." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/commercial-ac-not-cooling/", "/commercial-ac-problems/uneven-temperatures-hot-cold-spots/", "/commercial-ac-problems/high-energy-bills-long-runtime/", "/commercial-ac-problems/rooftop-unit-problems/" ], "safetyBoundary": "Do not enter roofs, ceiling spaces, electrical compartments, mechanical equipment or other controlled areas without authorization, training and applicable protection. Refrigerant, electrical, structural and code determinations belong to the responsible qualified provider.", "slug": "heat-balance", "sourceIds": [ "nist-single-room-heat-balance", "doe-building-energy-modeling-hvac" ], "terms": [ "Heat balance", "Heat gain", "Cooling load", "Sensible heat", "Thermal storage", "Supply air", "Return air", "Heat rejection" ], "title": "Why a Building Stays Hot: A Heat-Balance Primer" }, { "canonicalRoute": "/science/dew-point-condensation/", "description": "Understand why relative humidity alone cannot predict condensation and how moisture, air pathways and cold surfaces interact.", "eyebrow": "Moisture science \u00b7 Condensation risk", "lede": "Condensation becomes possible when moisture-bearing air reaches a surface at or below that air's dew-point temperature. Finding water is therefore the start of a pathway investigation, not proof that cooling equipment is the sole cause.", "limitations": [ "A relative-humidity reading alone cannot establish moisture content, surface condensation or source.", "A surface below measured dew point supports condensation potential at that time; it does not exclude simultaneous leaks or stored moisture.", "Infrared patterns are affected by emissivity, reflections, angle and hidden construction and are not proof of wet material.", "This article does not diagnose mold, determine occupant health effects or define a remediation scope." ], "measurements": [ "GCT field method 1 \u2014 Locate and time the moisture: record the exact surface or assembly, first observed time, duration, weather, occupancy and equipment state.", "GCT field method 2 \u2014 Measure coincident air conditions: record dry-bulb temperature and relative humidity, then obtain dew point with a documented method; identify the hygrometer, calibration status, stabilization time and position.", "GCT field method 3 \u2014 Measure the surface in \u00b0C (\u00b0F optional), recording material, finish, infrared emissivity setting or contact method. Treat reflective and low-emissivity surfaces with extra caution.", "GCT field method 4 \u2014 Trace accessible drainage, insulation continuity, visible bulk-water paths and pressure-driven air pathways without opening hazardous assemblies. Separate observations from hypotheses requiring destructive or specialist investigation.", "GCT field method 5 \u2014 Trend indoor and outdoor temperature, relative humidity or dew point, surface temperature and system state through the event and after any authorized correction. Preserve raw readings, gaps, sensor movement and uncertainty." ], "mechanism": [ "Literature summary: dew point is the temperature at which the existing water-vapor content would reach saturation during cooling at approximately constant pressure. Relative humidity changes with air temperature even when the amount of water vapor is unchanged, so dew point is often the clearer indicator of moisture available to condense.", "Condensation requires both a moisture source or pathway and a sufficiently cold surface. Supply diffusers, chilled piping, cold ducts, glass and interior finishes can cross the dew point when humid outdoor air, ventilation air, infiltration or indoor moisture reaches them.", "Moisture also moves as bulk water, vapor diffusion and air transport. A wet surface can result from plumbing, roof or envelope leakage, drain or condensate failure, capillary movement or condensation; visual similarity does not establish the source.", "Surface temperature, air temperature and moisture must be measured at the same location and time. Conditions can differ across a room, inside an assembly and during occupied versus unoccupied schedules, so a single central sensor can miss the critical interface." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/high-indoor-humidity/", "/commercial-ac-problems/water-condensate-leaks/", "/commercial-ac-problems/odors-indoor-air-quality/", "/commercial-ac-problems/building-pressure-door-problems/" ], "safetyBoundary": "Stop around energized wet equipment, suspected contaminated materials, damaged ceilings, confined spaces or structural hazards. Sampling, remediation, medical interpretation and invasive envelope work require the appropriate qualified professionals.", "slug": "dew-point-condensation", "sourceIds": [ "epa-moisture-control", "nist-psychrometric-algorithms", "nist-hygrometers" ], "terms": [ "Dew point", "Relative humidity", "Dry-bulb temperature", "Humidity ratio", "Vapor pressure", "Condensation", "Emissivity", "Infiltration" ], "title": "Dew Point, Surface Temperature and Condensation" }, { "canonicalRoute": "/science/sensible-latent-cooling/", "description": "Separate temperature reduction from moisture removal when evaluating comfort, coil performance, runtime and ventilation load.", "eyebrow": "Psychrometrics \u00b7 Temperature and moisture", "lede": "Cooling air and drying air are related but different tasks. A space can reach its temperature target while retaining excessive moisture, or remove moisture while still missing the sensible load during a peak condition.", "limitations": [ "Supply-to-return temperature difference alone is not total capacity and does not quantify latent removal.", "Condensate volume alone omits stored water, re-evaporation, leakage and changing entering conditions.", "Short field samples may not represent cycling, part-load or peak latent performance.", "Generic humidity or temperature targets cannot replace project requirements, local guidance or qualified design." ], "measurements": [ "GCT field method 1 \u2014 Capture equipment mode, fan and compressor state, runtime, setpoint, occupancy, outdoor condition and ventilation or door state using a common timestamp.", "GCT field method 2 \u2014 Measure dry-bulb temperature and relative humidity or dew point at representative entering and leaving air locations after stabilization, avoiding direct radiant influence, bypass air and unrepresentative grilles.", "GCT field method 3 \u2014 Confirm accessible condensate flow and drainage condition without treating drain volume as the entire latent balance; note fan cycling, possible re-evaporation and other water sources.", "GCT field method 4 \u2014 Use an appropriate measured airflow method or qualified balancing result before deriving sensible or total cooling rate. Mark assumed airflow as an assumption, not measured capacity.", "GCT field method 5 \u2014 After an authorized adjustment, repeat measurements under comparable load and runtime, reporting temperature and moisture outcomes separately with uncertainty." ], "mechanism": [ "Literature summary: sensible cooling lowers dry-bulb temperature. Latent cooling removes water vapor, usually when air is cooled below its dew point at a coil and liquid water drains away. Total cooling is the combined sensible and latent effect under the stated conditions.", "The sensible heat ratio describes the sensible portion of total cooling for a defined process. It is not a fixed property of every installation: entering-air condition, airflow, coil temperature, compressor operation and ventilation load can change the split.", "Airflow affects delivery and coil behavior. Excess or insufficient airflow, short cycling, staged capacity, fan operation after compressor shutdown and outdoor-air load can change temperature and moisture performance even when the thermostat appears satisfied.", "Psychrometric calculations require paired measurements and a defined pressure or altitude. Enthalpy or humidity-ratio differences support a total-capacity estimate only when airflow and sensor data are sufficiently reliable and taken across the same air stream." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/high-indoor-humidity/", "/commercial-ac-problems/commercial-ac-not-cooling/", "/commercial-ac-problems/weak-airflow-stuffy-building/", "/commercial-ac-problems/high-energy-bills-long-runtime/" ], "safetyBoundary": "Do not open refrigerant circuits, bypass safeties, reach into moving equipment or enter energized compartments. Airflow, charge and equipment-performance determinations requiring trade work remain with the responsible qualified provider.", "slug": "sensible-latent-cooling", "sourceIds": [ "nist-psychrometric-algorithms", "doe-hot-humid-humidity-control", "epa-moisture-control" ], "terms": [ "Sensible heat", "Latent heat", "Total cooling", "Sensible heat ratio", "Enthalpy", "Humidity ratio", "Dew point", "Condensate" ], "title": "Sensible and Latent Cooling: Temperature Is Only Part of the Load" }, { "canonicalRoute": "/science/airflow-building-pressure/", "description": "Trace supply, return, outdoor air, exhaust and leakage as one mass-balance system instead of treating a door or grille symptom in isolation.", "eyebrow": "Air systems \u00b7 Pressure-driven flow", "lede": "Air moves because pressure differs across a pathway. Fans, wind, temperature differences and openings interact, so a building can change from balanced to strongly negative or positive as equipment and doors change state.", "limitations": [ "A pressure snapshot can change with wind, buoyancy, doors and fan staging and may not represent another time.", "Smoke or tissue movement shows direction qualitatively; it does not measure airflow rate.", "Carbon-dioxide concentration is not a direct airflow measurement without source, occupancy and mixing assumptions.", "Changing exhaust or outdoor air can affect health, process, combustion and code requirements and is not a casual comfort adjustment." ], "measurements": [ "GCT field method 1 \u2014 Build an operating-state matrix listing supply, return, outdoor-air and exhaust equipment as on, off, staged or overridden; include doors, loading activity and process exhaust.", "GCT field method 2 \u2014 Define each pressure reference, zero and place the manometer according to its instructions, then record pascals (Pa; inches of water optional) with the sign convention.", "GCT field method 3 \u2014 Record door behavior, accessible leakage indications and supply-return relationships under each safe state. Label tissue or smoke-safe visualization as qualitative only.", "GCT field method 4 \u2014 Use a suitable airflow method for the opening or duct, recording instrument, geometry, correction factors and uncertainty. Do not combine incompatible estimates as a balanced survey.", "GCT field method 5 \u2014 Change only one authorized operating state, allow stabilization and repeat pressure, door and zone observations; restore the approved state and document unresolved ventilation or safety questions." ], "mechanism": [ "Literature summary: incoming and outgoing airflows must reconcile over time for a building or zone. Supply, return, outdoor air and exhaust are intentional flows; leakage through doors, cracks, ceilings and ducts can complete the balance unintentionally.", "Pressure difference drives air through available paths. Mechanical fans are one driver, while wind pressure and buoyancy from indoor-outdoor temperature difference can change direction and magnitude. A reading is meaningful only with a reference location and operating state.", "Negative pressure can draw untreated outdoor or adjacent-zone air inward; positive pressure can push conditioned air and moisture into assemblies. Either condition may redistribute odors, change door behavior and add sensible or latent load.", "A weak register may reflect fan performance, restriction, duct leakage, damper position, zone pressure or an inadequate return path. Measuring one outlet cannot establish which part of the network caused the symptom." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/building-pressure-door-problems/", "/commercial-ac-problems/weak-airflow-stuffy-building/", "/commercial-ac-problems/odors-indoor-air-quality/", "/commercial-ac-problems/uneven-temperatures-hot-cold-spots/" ], "safetyBoundary": "Do not disable required ventilation, exhaust, smoke control, fire doors, combustion safeguards or pressure relationships. Formal balancing, hazardous-area testing and code decisions require the responsible qualified professionals.", "slug": "airflow-building-pressure", "sourceIds": [ "nist-contam-user-guide", "nist-building-airflow-physics", "epa-building-air-quality-guide" ], "terms": [ "Airflow", "Pressure difference", "Infiltration", "Exfiltration", "Ventilation", "Outdoor air", "Exhaust air", "Return path" ], "title": "Airflow and Building Pressure: Follow the Complete Path" }, { "canonicalRoute": "/science/temporary-cooling-heat-rejection/", "description": "Evaluate the cold side, hot side, replacement air, condensate and electrical input before calling portable cooling a net building solution.", "eyebrow": "Temporary cooling \u00b7 Heat rejection", "lede": "A portable or temporary air conditioner moves heat rather than destroying it. The whole setup succeeds only when the collected indoor heat and the equipment's electrical input are rejected outside the boundary that is supposed to become cooler.", "limitations": [ "A nameplate or standardized rating does not equal installed performance in a different duct, pressure, temperature or humidity condition.", "A cold discharge stream can feel effective while the net building heat balance remains unchanged or worsens.", "A short temperature drop near the unit does not establish uniform zone cooling, moisture control or sustained performance.", "Temporary cooling does not correct the underlying load, airflow, controls or equipment fault unless that cause is separately addressed." ], "measurements": [ "GCT field method 1 \u2014 Define the cooling boundary and trace where condenser air, radiated equipment heat and condensate leave it. Do not use 'vented' without naming the actual termination.", "GCT field method 2 \u2014 Record model, rated condition, duct arrangement, electrical input, stated capacity metric and filter or hose condition; retain an authorized nameplate image and manufacturer-document reference.", "GCT field method 3 \u2014 Measure zone-to-reference pressure and indoor-outdoor temperature and dew point with the temporary unit off and on, noting door position, exhaust fans and other changed equipment.", "GCT field method 4 \u2014 Trend representative zone conditions, runtime, power, condensate status and hot-side temperature over a defined period. Keep zone sensors outside the direct cold-air jet.", "GCT field method 5 \u2014 Compare the result with a predeclared zone, duration, moisture, safety and operational criterion; record effects in adjacent zones and report inconclusive comparisons." ], "mechanism": [ "Literature summary: a vapor-compression cooler absorbs heat at the evaporator and rejects it at the condenser. The rejected rate includes the absorbed cooling load plus much of the electrical power consumed, so discharging hot air into the same building boundary cannot create equivalent net whole-building cooling.", "The boundary must be explicit. A unit may cool one occupied zone while warming a ceiling plenum or adjacent room; whether that is acceptable depends on where the heat ultimately goes and what other spaces, ducts, alarms or materials share that volume.", "Single-duct portable units commonly use conditioned room air for condenser cooling and exhaust it. That air must be replaced, often by warmer or more humid air entering through leakage paths, which can reduce net benefit and alter building pressure.", "Cooling below dew point produces condensate. Electrical supply, drain routing, overflow protection, duct resistance and hot-side clearance are parts of the temporary system, not secondary details." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/commercial-ac-not-cooling/", "/commercial-ac-problems/building-pressure-door-problems/", "/commercial-ac-problems/high-indoor-humidity/", "/commercial-ac-problems/high-energy-bills-long-runtime/" ], "safetyBoundary": "Use only approved electrical circuits, overcurrent protection, ducts, clearances and condensate controls. Do not discharge into concealed or occupied spaces without responsible review, and do not alter fire, smoke, combustion, egress or required ventilation systems.", "slug": "temporary-cooling-heat-rejection", "sourceIds": [ "doe-portable-air-conditioners", "doe-heat-pumps", "nist-contam-user-guide", "epa-moisture-control" ], "terms": [ "Evaporator", "Condenser", "Heat rejection", "Cooling boundary", "Replacement air", "Single-duct portable air conditioner", "Condensate", "Coefficient of performance" ], "title": "Temporary Cooling Works Only When Heat Leaves the Boundary" }, { "canonicalRoute": "/science/cooling-capacity-efficiency/", "description": "Read equipment ratings in context and separate heat-removal rate, electrical input, part-load behavior and installed delivery.", "eyebrow": "Equipment performance \u00b7 Ratings and reality", "lede": "Capacity asks how much heat can be removed under stated conditions. Efficiency relates useful cooling to energy input. Neither rating proves that an installed system delivers the needed result in a particular building.", "limitations": [ "This field workflow is not a DOE, manufacturer or laboratory certification test.", "Temperature split, suction-line feel, current draw or nameplate data alone cannot establish total capacity or refrigerant charge.", "Rated efficiency cannot be converted directly into site savings without a valid baseline, load profile, controls and energy measurement.", "One peak or part-load observation cannot represent all weather, occupancy and staging conditions." ], "measurements": [ "GCT field method 1 \u2014 Record manufacturer, model, configuration, nominal capacity, efficiency metric, rated conditions and the official or manufacturer test basis. Do not compare unlike metrics as if they used the same conditions.", "GCT field method 2 \u2014 Capture indoor and outdoor dry-bulb and moisture conditions, airflow state, fan and compressor stages, controls and runtime, stating whether the readings were simultaneous and stable.", "GCT field method 3 \u2014 When the decision requires it, use qualified methods to obtain airflow, entering and leaving air properties and electrical input; keep direct measurements separate from nameplate values and assumptions.", "GCT field method 4 \u2014 Calculate field indicators only when placement, airflow, psychrometric data and uncertainty support them. Describe deviations from rating conditions instead of declaring a pass or fail against an inapplicable point.", "GCT field method 5 \u2014 Relate operation to zone temperature, moisture, distribution, runtime and energy over a representative period, reporting capacity, efficiency and comfort as separate findings." ], "mechanism": [ "Literature summary: cooling capacity is a heat-removal rate, normally expressed in watts or kilowatts, with Btu/h or tons of refrigeration also common on U.S. equipment. Efficiency metrics compare output with input under defined test conditions; they are not interchangeable with capacity.", "Rated performance depends on entering indoor and outdoor conditions, airflow, fan-power treatment, staging and the specified test method. A seasonal or integrated metric weights defined conditions and is not a promise of exact efficiency at every field condition.", "Installed performance adds the building system: ducts, filters, coils, fans, dampers, controls, ventilation and heat rejection. A correctly rated unit can still miss the occupied result when distribution or controls are wrong, while oversizing can create cycling and moisture-control problems.", "Useful comparison begins with the actual load profile and acceptance target. Larger nominal capacity can increase first cost and change part-load operation; higher rated efficiency does not repair excess load, inadequate airflow or an incorrect sequence." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/commercial-ac-not-cooling/", "/commercial-ac-problems/high-energy-bills-long-runtime/", "/commercial-ac-problems/repeated-hvac-breakdowns/", "/commercial-ac-problems/rooftop-unit-problems/" ], "safetyBoundary": "Electrical, refrigerant, pressure, rotating-equipment and roof measurements require authorized qualified personnel and applicable protective practices. Never bypass safeties or infer a refrigerant adjustment from this article.", "slug": "cooling-capacity-efficiency", "sourceIds": [ "doe-light-commercial-efficiency", "doe-commercial-unitary-air-conditioners", "doe-building-energy-modeling-hvac" ], "terms": [ "Cooling capacity", "Coefficient of performance", "Energy efficiency ratio", "Integrated energy efficiency ratio", "Part-load performance", "Rated condition", "Installed performance", "Cooling load" ], "title": "Cooling Capacity and Efficiency Are Different Questions" }, { "canonicalRoute": "/science/measurement-uncertainty/", "description": "Define the measurand, preserve operating context and report instrument, sampling and calculation limits instead of false precision.", "eyebrow": "Field metrology \u00b7 Evidence quality", "lede": "Every field value is an estimate tied to a method. Useful records show what was measured, where, when, with which instrument, under which operating state and with enough uncertainty information to support the decision being made.", "limitations": [ "This simplified process does not satisfy laboratory accreditation or contract-specific measurement requirements by itself.", "Repeated agreement can coexist with shared bias, wrong placement or an incorrectly defined measurand.", "Calibration status does not remove sampling, method, environmental or model uncertainty.", "A threshold comparison is weak when uncertainty is large relative to the distance from the threshold." ], "measurements": [ "GCT field method 1 \u2014 State the decision the data will inform and define the quantity, location, time window, operating state and required discrimination before collecting numbers.", "GCT field method 2 \u2014 Choose a suitable instrument and method, recording make, model, serial or asset ID, range, resolution and calibration status. A manufacturer specification is not proof of current calibration.", "GCT field method 3 \u2014 Document sensor position, contact, shielding, stabilization, sampling interval and simultaneous system state, including movement, interruption or environmental disturbance.", "GCT field method 4 \u2014 Take enough repeat observations and use an independent check when the result is near a decision threshold. Preserve all readings rather than removing inconvenient values without a documented technical reason.", "GCT field method 5 \u2014 State important uncertainty contributors, calculation assumptions and a suitable interval or qualitative confidence when a full budget is not justified; round the result consistently with supported uncertainty." ], "mechanism": [ "Literature summary: the measurand is the quantity intended to be measured, defined specifically enough that different observers understand the same target. 'Room temperature' is incomplete without location, height, time, sensor exposure and operating state.", "Instrument resolution, accuracy specification, calibration, drift, placement, stabilization, observer technique and environmental variation can all contribute to uncertainty. A display with more digits does not make the underlying result more certain.", "Repeated readings help reveal short-term variation but do not automatically expose systematic effects. Comparison with a reference, calibration information and a defensible method may be needed when the decision margin is small.", "Derived results inherit uncertainty from inputs and model. Capacity calculated from airflow and enthalpy difference can be far less certain than either displayed input, particularly when airflow or humidity varies across the stream." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/thermostat-controls-not-working/", "/commercial-ac-problems/uneven-temperatures-hot-cold-spots/", "/commercial-ac-problems/high-indoor-humidity/", "/commercial-ac-problems/repeated-hvac-breakdowns/" ], "safetyBoundary": "The desire for a better reading never authorizes exposure to energized parts, rotating machinery, refrigerant, roofs, contaminated areas or other hazards. Use remote, indirect or qualified methods when direct access is unsafe.", "slug": "measurement-uncertainty", "sourceIds": [ "nist-tn-1297", "nist-sp-811", "nist-hygrometers" ], "terms": [ "Measurand", "Measurement uncertainty", "Accuracy", "Resolution", "Calibration", "Repeatability", "Reproducibility", "Systematic effect" ], "title": "Measurement Uncertainty: Report What the Reading Can Support" }, { "canonicalRoute": "/science/commissioning-verification/", "description": "Turn requirements into functional tests, acceptance evidence, corrections and repeatable records across the operating modes that matter.", "eyebrow": "Quality process \u00b7 Functional performance", "lede": "Installation is not the same as verified operation. Commissioning connects owner requirements, design intent, sequences, equipment, controls, documentation and occupied outcomes through planned tests and recorded acceptance criteria.", "limitations": [ "This article does not define a full project commissioning plan, design review, balancing scope or code inspection.", "Passing one mode or season does not prove operation under untested weather, occupancy, alarm or failure conditions.", "Commissioning evidence does not by itself quantify energy savings; savings require an appropriate baseline and M&V method.", "A GCT-organized record is not a third-party certification and does not replace authority assigned by contract or law." ], "measurements": [ "GCT field method 1 \u2014 Record the owner or project requirement, responsible party, test condition, expected response and measurable pass criterion, separating comfort, equipment function, code obligations and savings claims.", "GCT field method 2 \u2014 Assemble current equipment identity, drawings, sequences, schedules, setpoints, prior changes, balancing data and unresolved issues; mark missing, superseded and unverified documents.", "GCT field method 3 \u2014 Confirm safe access, instrument suitability, calibration status, installation completion and that prerequisite defects do not invalidate the test. Do not force a functional test through an unsafe or incomplete system.", "GCT field method 4 \u2014 Under authorized control, command or observe defined modes and record commands, physical responses, timing, alarms, zone conditions and exceptions; preserve raw trends and identify who controlled the system.", "GCT field method 5 \u2014 Log each issue, responsible party and disposition, repeat the failed test after correction and record final status, remaining limits and monitoring needs. Work performed alone does not close an issue." ], "mechanism": [ "Literature summary: commissioning is a quality-assurance process that verifies systems are installed and operate according to defined requirements. It is strongest when acceptance criteria, responsibilities and test methods are written before the result is known.", "Functional testing checks cause and response across relevant modes: occupied and unoccupied schedules, staging, alarms, safeties, ventilation, cooling, recovery and failure response. A screen command is not proof that a damper, fan, valve or zone physically responded.", "Issues remain open until correction and retest. Replacing a component can restore operation without restoring sequence, airflow, moisture control or the occupied result, so evidence should connect the repair to the original requirement.", "Measurement and verification addresses performance after implementation. Baselines, boundary conditions and operating changes matter; commissioning proves intended function, while energy-savings claims require a separate suitable M&V plan." ], "modified": "2026-10-06", "published": "2026-10-06", "relatedRoutes": [ "/commercial-ac-problems/thermostat-controls-not-working/", "/commercial-ac-problems/repeated-hvac-breakdowns/", "/commercial-ac-problems/high-energy-bills-long-runtime/", "/commercial-ac-problems/commercial-ac-not-cooling/", "/commercial-ac-problems/rooftop-unit-problems/" ], "safetyBoundary": "Functional tests must be planned and controlled by authorized people. Never defeat equipment safeties, life-safety systems, interlocks, ventilation requirements or occupant protections to complete a test.", "slug": "commissioning-verification", "sourceIds": [ "doe-commissioning-process", "doe-hvac-commissioning", "doe-measurement-verification-options" ], "terms": [ "Commissioning", "Functional performance test", "Acceptance criterion", "Baseline", "Measurement and verification", "Operational verification", "Sequence of operation", "Issue log" ], "title": "Commissioning and Verification: Prove the Intended Operation" } ], "canonicalBase": "https://icy.ac/science/", "fieldRecord": { "columns": [ { "description": "Unique immutable identifier for this observation or calculation.", "name": "recordId", "unit": "none" }, { "description": "Non-sensitive project or study identifier.", "name": "projectReference", "unit": "none" }, { "description": "Repeatable location reference without unnecessary public identity.", "name": "siteZone", "unit": "none" }, { "description": "One of literature_summary, gct_field_method, field_observation, qualified_trade_finding, owner_report or derived_calculation.", "name": "sourceClass", "unit": "none" }, { "description": "Quantity, event, document or operating response recorded.", "name": "observationType", "unit": "none" }, { "description": "ISO 8601 local timestamp for the observation.", "name": "dateTimeLocal", "unit": "ISO 8601" }, { "description": "UTC offset associated with dateTimeLocal, such as -05:00.", "name": "utcOffset", "unit": "hh:mm" }, { "description": "Observer role only; 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create a new row linked to the earlier record.", "Use ISO 8601 local date and time plus an explicit UTC offset, and synchronize instruments when sequence matters.", "Record SI values first. Put optional U.S. customary equivalents in a separate clearly labeled field or note.", "Choose one source class: literature summary, GCT field method, field observation, qualified-trade finding, owner report or derived calculation.", "Keep raw readings separate from calculations. Preserve formulas, input record IDs, conversions and assumptions for every derived value.", "Use null for a measurement not taken and explain an omission that affects interpretation. Zero is a measured value, not a blank.", "Identify instrument and calibration status, state dominant uncertainty contributors and do not report more digits than the method supports.", "Record equipment, controls, occupancy, doors and exhaust state with every environmental reading that depends on operation.", "Use non-sensitive project and zone references. Do not place customer identity, personal data, credentials or security-sensitive building details in a public record.", "Separate observed facts, reported statements, interpretations and recommended next actions.", "Record the safety boundary and stop condition. A missing measurement is preferable to an unauthorized or hazardous one.", "Close an issue only against a declared acceptance criterion, preserving failed, inconclusive and no-change results." ], "introduction": "Use one row for one direct observation or one derived result. The record preserves operating context, source class, instrument identity and uncertainty without converting screening observations into an unsupported diagnosis.", "title": "ICY Cooling Science Field Record" }, "glossary": [ { "definition": "A result, tolerance or observable condition declared before a test and used to decide whether a requirement was met.", "relatedArticleSlugs": [ "commissioning-verification", "temporary-cooling-heat-rejection" ], "term": "Acceptance criterion" }, { "definition": "Closeness of agreement between a measured value and the value of the quantity being measured; it is not a synonym for resolution.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Accuracy" }, { "definition": "Movement rate of air through a defined area or path, reported in a suitable volume or mass flow unit such as L/s or kg/s.", "relatedArticleSlugs": [ "airflow-building-pressure", "sensible-latent-cooling", "cooling-capacity-efficiency" ], "term": "Airflow" }, { "definition": "The documented pre-change condition used for comparison, including relevant weather, occupancy, schedule and operating assumptions.", "relatedArticleSlugs": [ "commissioning-verification", "measurement-uncertainty" ], "term": "Baseline" }, { "definition": "An operation that establishes the relationship between an instrument's indication and reference quantity values under stated conditions.", "relatedArticleSlugs": [ "measurement-uncertainty", "dew-point-condensation" ], "term": "Calibration" }, { "definition": "A dimensionless ratio of useful heating or cooling effect to required energy input for stated conditions.", "relatedArticleSlugs": [ "cooling-capacity-efficiency", "temporary-cooling-heat-rejection" ], "term": "Coefficient of performance" }, { "definition": "A quality-assurance process used to verify that building systems are installed and operate according to defined project or owner requirements.", "relatedArticleSlugs": [ "commissioning-verification" ], "term": "Commissioning" }, { "definition": "Liquid formed when water vapor condenses; in cooling systems it commonly forms on a coil operating below the entering air's dew point.", "relatedArticleSlugs": [ "dew-point-condensation", "sensible-latent-cooling", "temporary-cooling-heat-rejection" ], "term": "Condensate" }, { "definition": "Phase change from vapor to liquid, possible when moisture-bearing air reaches a surface at or below the relevant dew-point temperature.", "relatedArticleSlugs": [ "dew-point-condensation" ], "term": "Condensation" }, { "definition": "The heat exchanger at which refrigerant rejects heat to an external sink and condenses during a conventional cooling cycle.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection", "cooling-capacity-efficiency" ], "term": "Condenser" }, { "definition": "The explicitly defined space or system boundary across which heat transfer is being evaluated.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection", "heat-balance" ], "term": "Cooling boundary" }, { "definition": "Rate at which a system removes heat under stated conditions, normally expressed in W or kW; Btu/h may appear on U.S. equipment.", "relatedArticleSlugs": [ "cooling-capacity-efficiency", "sensible-latent-cooling" ], "term": "Cooling capacity" }, { "definition": "Rate of heat removal needed to maintain a defined indoor condition under stated weather, occupancy and use.", "relatedArticleSlugs": [ "heat-balance", "cooling-capacity-efficiency" ], "term": "Cooling load" }, { "definition": "Temperature at which the existing water-vapor content would reach saturation during cooling at approximately constant pressure.", "relatedArticleSlugs": [ "dew-point-condensation", "sensible-latent-cooling", "temporary-cooling-heat-rejection" ], "term": "Dew point" }, { "definition": "Ordinary air temperature measured by a sensor shielded from moisture and inappropriate radiant influence.", "relatedArticleSlugs": [ "dew-point-condensation", "sensible-latent-cooling", "heat-balance" ], "term": "Dry-bulb temperature" }, { "definition": "A surface property describing thermal-radiation emission relative to an ideal blackbody; it materially affects infrared temperature measurement.", "relatedArticleSlugs": [ "dew-point-condensation", "measurement-uncertainty" ], "term": "Emissivity" }, { "definition": "A cooling-output-to-electric-input rating for defined test conditions, commonly expressed in Btu/(W\u00b7h) in U.S. equipment literature.", "relatedArticleSlugs": [ "cooling-capacity-efficiency" ], "term": "Energy efficiency ratio" }, { "definition": "A thermodynamic property useful for representing the sensible and latent energy of moist air relative to a defined reference.", "relatedArticleSlugs": [ "sensible-latent-cooling", "cooling-capacity-efficiency" ], "term": "Enthalpy" }, { "definition": "The heat exchanger at which refrigerant absorbs heat and evaporates during a conventional cooling cycle.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection", "sensible-latent-cooling" ], "term": "Evaporator" }, { "definition": "Uncontrolled outward air movement through openings or leakage paths in a building enclosure.", "relatedArticleSlugs": [ "airflow-building-pressure" ], "term": "Exfiltration" }, { "definition": "Air intentionally removed from a building or zone and discharged outside the defined boundary.", "relatedArticleSlugs": [ "airflow-building-pressure", "temporary-cooling-heat-rejection" ], "term": "Exhaust air" }, { "definition": "A planned test that observes whether a system produces the required physical response across defined operating modes.", "relatedArticleSlugs": [ "commissioning-verification" ], "term": "Functional performance test" }, { "definition": "Accounting of heat-transfer rates entering, leaving and accumulating within a defined boundary.", "relatedArticleSlugs": [ "heat-balance", "temporary-cooling-heat-rejection" ], "term": "Heat balance" }, { "definition": "Heat-transfer rate added to a building or zone through envelope, solar, outdoor-air or internal sources.", "relatedArticleSlugs": [ "heat-balance" ], "term": "Heat gain" }, { "definition": "Transfer of absorbed heat, plus relevant equipment input, from a cooling system to an external sink.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection", "heat-balance" ], "term": "Heat rejection" }, { "definition": "Mass of water vapor associated with a unit mass of dry air, commonly expressed as kg/kg of dry air.", "relatedArticleSlugs": [ "dew-point-condensation", "sensible-latent-cooling" ], "term": "Humidity ratio" }, { "definition": "Uncontrolled inward air movement through openings or leakage paths in a building enclosure.", "relatedArticleSlugs": [ "airflow-building-pressure", "dew-point-condensation", "heat-balance" ], "term": "Infiltration" }, { "definition": "Operation of equipment as part of the actual building, including distribution, controls, loads and boundary conditions.", "relatedArticleSlugs": [ "cooling-capacity-efficiency", "commissioning-verification" ], "term": "Installed performance" }, { "definition": "A commercial cooling-efficiency metric combining performance at specified load points using defined weighting.", "relatedArticleSlugs": [ "cooling-capacity-efficiency" ], "term": "Integrated energy efficiency ratio" }, { "definition": "A controlled record of a deficiency, its evidence, responsible party, disposition, retest and final status.", "relatedArticleSlugs": [ "commissioning-verification" ], "term": "Issue log" }, { "definition": "Energy associated with a phase change; in air-conditioning work it commonly refers to moisture removal or addition rather than dry-bulb change alone.", "relatedArticleSlugs": [ "sensible-latent-cooling", "dew-point-condensation" ], "term": "Latent heat" }, { "definition": "The quantity intended to be measured, defined with the conditions needed to make the result unambiguous.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Measurand" }, { "definition": "A planned process for determining and documenting performance or savings using a stated baseline, boundary and method.", "relatedArticleSlugs": [ "commissioning-verification" ], "term": "Measurement and verification" }, { "definition": "A parameter describing the dispersion of quantity values that could reasonably be attributed to a measurand.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Measurement uncertainty" }, { "definition": "Confirmation through observation and measurement that installed equipment is present, commissioned and capable of intended operation.", "relatedArticleSlugs": [ "commissioning-verification" ], "term": "Operational verification" }, { "definition": "Air intentionally brought from outdoors into a building or system, distinct from uncontrolled infiltration.", "relatedArticleSlugs": [ "airflow-building-pressure", "heat-balance" ], "term": "Outdoor air" }, { "definition": "Capacity and efficiency behavior when equipment operates below full rated load or in cycling or staged modes.", "relatedArticleSlugs": [ "cooling-capacity-efficiency", "sensible-latent-cooling" ], "term": "Part-load performance" }, { "definition": "Pressure at one point relative to a defined reference, commonly reported in pascals for building diagnostics.", "relatedArticleSlugs": [ "airflow-building-pressure", "temporary-cooling-heat-rejection" ], "term": "Pressure difference" }, { "definition": "The prescribed input and operating conditions under which a published equipment rating was determined.", "relatedArticleSlugs": [ "cooling-capacity-efficiency", "temporary-cooling-heat-rejection" ], "term": "Rated condition" }, { "definition": "A measure of water-vapor content relative to saturation at the same temperature and pressure, expressed as a percentage.", "relatedArticleSlugs": [ "dew-point-condensation", "sensible-latent-cooling" ], "term": "Relative humidity" }, { "definition": "Closeness of agreement among results obtained under the same specified measurement conditions over a short interval.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Repeatability" }, { "definition": "Air entering a zone or building to replace air that has been exhausted or otherwise removed.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection", "airflow-building-pressure" ], "term": "Replacement air" }, { "definition": "Closeness of agreement among results obtained under changed conditions such as operator, instrument or location.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Reproducibility" }, { "definition": "Smallest change in a quantity that produces a perceptible change in an instrument indication.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Resolution" }, { "definition": "Air removed from a conditioned space and conveyed back toward air-handling equipment.", "relatedArticleSlugs": [ "heat-balance", "sensible-latent-cooling" ], "term": "Return air" }, { "definition": "The intended and unintended route by which air leaves a supplied zone and returns to the air-handling system or another reference space.", "relatedArticleSlugs": [ "airflow-building-pressure", "heat-balance" ], "term": "Return path" }, { "definition": "Energy transfer associated with dry-bulb temperature change without accounting for phase-change energy.", "relatedArticleSlugs": [ "sensible-latent-cooling", "heat-balance" ], "term": "Sensible heat" }, { "definition": "Ratio of sensible cooling to total cooling for a stated air-conditioning process and condition.", "relatedArticleSlugs": [ "sensible-latent-cooling" ], "term": "Sensible heat ratio" }, { "definition": "Documented logic defining how controls and equipment respond to conditions, schedules, commands, limits and alarms.", "relatedArticleSlugs": [ "commissioning-verification", "cooling-capacity-efficiency" ], "term": "Sequence of operation" }, { "definition": "A portable unit that rejects condenser air through one duct and commonly draws that air from the conditioned space, creating a replacement-air requirement.", "relatedArticleSlugs": [ "temporary-cooling-heat-rejection" ], "term": "Single-duct portable air conditioner" }, { "definition": "Air delivered by a mechanical system to a building zone.", "relatedArticleSlugs": [ "heat-balance", "airflow-building-pressure", "sensible-latent-cooling" ], "term": "Supply air" }, { "definition": "A repeatable influence that can shift measurement results in a consistent direction and may not be revealed by repetition alone.", "relatedArticleSlugs": [ "measurement-uncertainty" ], "term": "Systematic effect" }, { "definition": "Energy accumulated in or released from building air, contents or assemblies as their temperatures change.", "relatedArticleSlugs": [ "heat-balance" ], "term": "Thermal storage" }, { "definition": "Combined sensible and latent heat-removal rate for a stated air process and operating condition.", "relatedArticleSlugs": [ "sensible-latent-cooling", "cooling-capacity-efficiency" ], "term": "Total cooling" }, { "definition": "Partial pressure exerted by water vapor within a gas mixture.", "relatedArticleSlugs": [ "dew-point-condensation" ], "term": "Vapor pressure" }, { "definition": "Intentional supply or removal of air to or from a space for indoor-environmental or process purposes.", "relatedArticleSlugs": [ "airflow-building-pressure", "heat-balance" ], "term": "Ventilation" } ], "lastReviewed": "2026-10-06", "publicPolicy": { "contentClasses": { "fieldObservation": "A time-, place-, instrument- and operating-state-specific record. An observation is not automatically a diagnosis or a general result.", "gctFieldMethod": "A practical sequence for recording conditions, separating hypotheses and checking whether a controlled change produced the intended result. It is an operational method, not a consensus standard or a substitute for a licensed trade or design professional.", "illustratedExample": "A clearly labeled hypothetical or teaching example. It must never be described as customer history, measured savings or completed field work.", "literatureSummary": "A plain-language synthesis of the identified official sources. It must retain material conditions and limitations and must not be presented as an original GCT discovery.", "qualifiedTradeFinding": "A finding attributed to the responsible qualified provider, with scope and evidence preserved. ICY does not silently adopt it as its own credentialed determination." }, "position": "ICY AC publishes plain-English building-cooling science and a practical evidence-organizing workflow. The articles are educational material, not peer-reviewed original research, engineered design, a cooling-load calculation, a commissioning certification, a code determination, a medical or indoor-environmental diagnosis, or proof that a particular repair is required.", "privacy": "Public records omit customer identity, precise site identity, personal data and security-sensitive building information unless current documented permission and a defined publication purpose exist.", "requirements": [ "Every science article must say which statements summarize literature and which steps are the GCT field method.", "Do not invent customers, jobs, measurements, savings, response times, credentials, licenses, certifications, reviews or field outcomes.", "Do not turn association into causation. State what a measurement supports and what it cannot establish alone.", "Do not promise comfort, energy savings, equipment life, payback or code compliance from a generic method.", "Use named official sources for material scientific claims and review sources whenever an article is materially revised.", "Mark synthetic or illustrative media as illustrative whenever a reasonable reader could mistake it for real field evidence.", "List only verifiable authorship, organizational roles and review activity. Do not disguise the absence of a named licensed reviewer.", "Correct substantive errors transparently, retaining the prior publication date and recording the modified date.", "Publish real field examples only with an appropriate consent and privacy review; otherwise use a clearly labeled de-identified or hypothetical example." ], "rights": "This library asserts no open-license rights in external sources and grants no unrecorded reuse rights in GCT or ICY material. External material is cited and linked; quotation or reuse must follow the source owner's terms and applicable law.", "safety": "Educational measurements stop at electrical, refrigerant, roof, structural, combustion, contaminated-material, biological, confined-space and other hazards. Work requiring authorization, training, permits or a licensed trade remains with the responsible qualified provider.", "sourceMaintenance": "Prefer durable official landing pages or publications with stable identifiers. Check links and claims at each recorded review and replace moved or withdrawn material without changing the historical meaning of a citation.", "unitRule": "Use SI first. U.S. customary equivalents may follow where they help readers interpret installed equipment or field instruments. State the quantity, unit, instrument and operating condition, and do not turn a rough observation into false precision." }, "publicationDate": "2026-10-06", "schema": "gct-icy-science-library-v1", "sources": [ { "id": "nist-single-room-heat-balance", "organization": "National Institute of Standards and Technology", "supports": [ "Heat-balance foundation", "envelope and solar gains", "surface and air heat transfer", "HVAC load relationships" ], "title": "Single-Room Heat Balance for Building Heat Transfer", "url": "https://www.nist.gov/publications/single-room-heat-balance-building-heat-transfer" }, { "id": "doe-building-energy-modeling-hvac", "organization": "U.S. Department of Energy", "supports": [ "Cooling-load categories", "building and HVAC interaction", "equipment selection", "controls" ], "title": "Building Energy Modeling 101: HVAC Design and Operation Use Case", "url": "https://www.energy.gov/cmei/buildings/articles/building-energy-modeling-101-hvac-design-and-operation-use-case" }, { "id": "epa-moisture-control", "organization": "U.S. Environmental Protection Agency", "supports": [ "Dew point", "condensation", "moisture transport", "HVAC moisture control", "verification" ], "title": "Moisture Control Guidance for Building Design, Construction and Maintenance", "url": "https://www.epa.gov/indoor-air-quality-iaq/moisture-control-guidance-building-design-construction-and-maintenance-0" }, { "id": "nist-psychrometric-algorithms", "organization": "National Institute of Standards and Technology", "supports": [ "Psychrometrics", "moist-air properties", "humidity ratio", "enthalpy" ], "title": "Algorithms for Psychrometric Calculations (Skeleton Tables for the Thermodynamic Properties of Moist Air)", "url": "https://www.nist.gov/publications/algorithms-psychometric-calculations-skeleton-tables-thermodynamic-properties-moist-air" }, { "id": "doe-hot-humid-humidity-control", "organization": "U.S. Department of Energy", "supports": [ "Sensible and latent loads", "dehumidification", "part-load moisture behavior", "airflow and controls" ], "title": "Advanced HVAC Humidity Control for Hot-Humid Climates", "url": "https://www.energy.gov/cmei/buildings/advanced-hvac-humidity-control-hot-humid-climates-0" }, { "id": "nist-contam-user-guide", "organization": "National Institute of Standards and Technology", "supports": [ "Pressure-driven airflow", "infiltration and exfiltration", "wind and buoyancy", "fan and interzonal flow" ], "title": "CONTAM User Guide and Program Documentation Version 3.4", "url": "https://www.nist.gov/publications/contam-user-guide-and-program-documentation-version-34" }, { "id": "nist-building-airflow-physics", "organization": "National Institute of Standards and Technology", "supports": [ "Pressure differences", "wind", "buoyancy", "building pressurization and depressurization" ], "title": "Building Airflow Physics", "url": "https://www.nist.gov/video/building-airflow-physics" }, { "id": "epa-building-air-quality-guide", "organization": "U.S. Environmental Protection Agency and National Institute for Occupational Safety and Health", "supports": [ "Commercial-building investigation", "HVAC pathways", "recordkeeping", "indoor-air-quality boundaries" ], "title": "Building Air Quality Guide: A Guide for Building Owners and Facility Managers", "url": "https://www.epa.gov/indoor-air-quality-iaq/building-air-quality-guide-guide-building-owners-and-facility-managers" }, { "id": "doe-portable-air-conditioners", "organization": "U.S. Department of Energy", "supports": [ "Portable-air-conditioner scope", "cooling-capacity ratings", "energy use", "test procedures" ], "title": "Portable Air Conditioners", "url": "https://www.energy.gov/cmei/buildings/portable-air-conditioners" }, { "id": "doe-heat-pumps", "organization": "U.S. Department of Energy", "supports": [ "Heat transfer", "heat sources and sinks", "cooling-cycle overview", "heat rejection" ], "title": "Heat Pumps", "url": "https://www.energy.gov/heat-pumps" }, { "id": "doe-light-commercial-efficiency", "organization": "U.S. Department of Energy Federal Energy Management Program", "supports": [ "Cooling-capacity bands", "efficiency metrics", "energy use", "life-cycle comparison" ], "title": "Purchasing Energy-Efficient Light Commercial Heating and Cooling Equipment", "url": "https://www.energy.gov/cmei/femp/purchasing-energy-efficient-light-commercial-heating-and-cooling-equipment" }, { "id": "doe-commercial-unitary-air-conditioners", "organization": "U.S. Department of Energy", "supports": [ "Commercial equipment definitions", "IEER and COP", "rating conditions", "current test procedures" ], "title": "Air-Cooled Unitary Air Conditioners and Heat Pumps", "url": "https://www.energy.gov/cmei/buildings/air-cooled-unitary-air-conditioners-and-heat-pumps" }, { "id": "nist-tn-1297", "organization": "National Institute of Standards and Technology", "supports": [ "Measurand definition", "Type A and Type B uncertainty", "combined uncertainty", "uncertainty reporting" ], "title": "NIST Technical Note 1297: Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results", "url": "https://www.nist.gov/pml/nist-technical-note-1297" }, { "id": "nist-sp-811", "organization": "National Institute of Standards and Technology", "supports": [ "SI units", "quantity symbols", "unit conversion", "measurement reporting" ], "title": "NIST Special Publication 811: Guide for the Use of the International System of Units", "url": "https://www.nist.gov/pml/special-publication-811" }, { "id": "nist-hygrometers", "organization": "National Institute of Standards and Technology", "supports": [ "Humidity measurement", "dew point", "relative humidity", "calibration context" ], "title": "Hygrometers", "url": "https://www.nist.gov/pml/sensor-science/thermodynamic-metrology/hygrometers" }, { "id": "doe-commissioning-process", "organization": "U.S. Department of Energy Federal Energy Management Program", "supports": [ "Commissioning planning", "investigation", "implementation and retest", "handoff and ongoing verification" ], "title": "Commissioning Process for Federal Facilities", "url": "https://www.energy.gov/cmei/femp/commissioning-process-federal-facilities" }, { "id": "doe-hvac-commissioning", "organization": "U.S. Department of Energy", "supports": [ "Functional verification", "equipment and controls", "dampers and schedules", "ventilation and delivered airflow" ], "title": "HVAC Commissioning", "url": "https://www.energy.gov/cmei/buildings/hvac-commissioning" }, { "id": "doe-measurement-verification-options", "organization": "U.S. Department of Energy Federal Energy Management Program", "supports": [ "Baselines", "retrofit isolation", "whole-building verification", "calibrated simulation" ], "title": "Measurement and Verification Options for Federal Energy- and Water-Saving Projects", "url": "https://www.energy.gov/cmei/femp/measurement-and-verification-options-federal-energy-and-water-saving-projects" } ], "version": "1.0" }