{"hq_id":"hq-p-spe-000122","name":"Parking Garage Air Quality (Vehicle Exhaust Infiltration, PM2.5, NO2, CO)","category":{"primary":"specialized","secondary":"office","tags":["parking garage","vehicle exhaust","PM2.5","NO2","CO","ventilation","infiltration","office"]},"product_tier":"SPE","overall_risk_level":"moderate","description":"Parking garages attached to or below office buildings are a significant source of vehicle exhaust infiltration: PM2.5, NO2, CO, benzene, formaldehyde, and ultrafine particles from engine idling, cold starts, and tire/brake wear. Underground garages: mechanical ventilation required (IBC/IMC: 0.75 CFM/sq ft or CO-sensor-based demand ventilation). Exhaust infiltration pathways: elevator shafts, stairwells, HVAC outdoor air intakes located near garage exhaust, and pressure differentials pulling garage air into adjacent retail/office. CO is the acute concern (garage CO alarm standard: 35 ppm for 1-hour, 200 ppm immediate action). NO2 and PM2.5: chronic health concern for workers stationed in garages (attendants, valets, security). EV transition: will eventually eliminate tailpipe emissions in garages but not tire/brake particulate.","synthesis":{"derived_risk_level":"extreme","synthesis_confidence":0.757,"synthesis_method":"compound_composition","context_used":"human_adult","context_source":"product_users","exposure_modifier":1.265,"vulnerability_escalated":false,"escalation_reason":null,"compounds_resolved":1,"compounds_total":1,"synthesis_date":"2026-05-09","synthesis_version":"1.2.0","methodology_note":"exposure_modifier and adjusted_magnitude are computed from ALETHEIA-calibrated heuristics (route × duration × frequency multipliers, clamped to [0.5, 1.4]). Multipliers are directionally informed by EPA Exposure Factors Handbook (2011) and CalEPA OEHHA but are not regulatory consensus. See /api/methodology for full disclosure."},"hazard_summary":{"sensitive_populations":"garage workers (chronic exposure), pregnant commuters, asthmatics","overall_risk":"moderate","primary_concerns":["Vehicle exhaust infiltration from garage into adjacent office/retail","Garage workers: chronic exposure to PM2.5, NO2, CO, benzene","Underground garages with inadequate ventilation (CO buildup)","Building HVAC intakes near garage exhaust (infiltration pathway)"],"exposure_routes":"Inhalation (vehicle exhaust: PM2.5, NO2, CO, benzene, ultrafine particles)"},"exposure":{"routes":["inhalation"],"contact_types":["inhalation"],"users":["adult"],"duration":"minutes_to_hours","frequency":"daily","scenarios":["Walking through parking garage to office (daily commute exposure)","Garage exhaust infiltrating into adjacent office/retail via elevator shaft","Garage attendants/valets: chronic exhaust exposure (occupational)","Underground garage with inadequate ventilation (CO buildup)"],"notes":"IBC/IMC ventilation requirement: 0.75 CFM/sq ft for enclosed parking garages, or CO/NO2 sensor-based demand ventilation (DCV). CO sensors: garage alarm at 35 ppm (ASHRAE 62.1 garage ventilation trigger). OSHA PEL: CO 50 ppm (8-hr TWA). Garage HVAC intake: building outdoor air intakes must be located away from garage exhaust discharge — IBC requires minimum separation distance. Pressure relationships: garage should be maintained at negative pressure relative to adjacent occupied spaces (prevents infiltration). EV charging in garages: no tailpipe emissions but thermal runaway fire risk from Li-ion batteries is emerging concern for garage design."},"consumer_guidance":{"usage_warning":"If you smell exhaust in your office: report to building management immediately (garage infiltration pathway). Minimize time in enclosed parking garages (don't idle, proceed directly). Garage workers: request CO and NO2 monitoring. Building managers: verify HVAC outdoor air intakes are not near garage exhaust. Verify garage is at negative pressure relative to occupied spaces.","safer_alternatives":["CO and NO2 sensor-based demand ventilation in garage","Building HVAC intakes separated from garage exhaust","Garage maintained at negative pressure relative to occupied spaces","EV parking priority near building entrance (zero tailpipe at point of entry)"]},"regulatory":{"applicable_regulations":[{"jurisdiction":"USA","regulation":"IBC/IMC Parking Garage Ventilation + OSHA CO PEL","citation":"IBC 406; IMC 403.3; ASHRAE 62.1-2022; 29 CFR 1910.1000","requirements":"IBC/IMC: enclosed parking 0.75 CFM/sq ft or CO/NO2 sensor-based DCV. ASHRAE 62.1: CO sensor trigger at 35 ppm. OSHA: CO PEL 50 ppm (8-hr TWA). Building HVAC intake separation from garage exhaust per IBC.","compliance_status":null,"effective_date":null,"enforcing_agency":"Local building codes / OSHA","penalties":null,"source_ref":null}],"certifications":[],"labeling":{"required_disclosures":[],"prop65_warning":{"required":null,"chemicals":[],"endpoint":null,"notes":null},"ghs_labeling":{"required":null,"signal_word":null,"pictograms":[],"hazard_statements":[],"notes":null},"hidden_ingredients":{"trade_secret_protected":null,"categories_hidden":[],"estimated_count":null,"known_concerns":null,"notes":null},"notes":null},"recalls":[],"regulatory_gap":null,"notes":null},"lifecycle":{"recyclable":false,"disposal_guidance":"N/A — building infrastructure.","hazardous_waste":false,"expected_lifespan":"varies"},"formulation":{"form":"varies","key_ingredients":[],"certifications":[]},"materials":{"common":[],"concerning":[],"preferred":[]},"compound_composition":[{"hq_id":"hq-c-org-000010","compound_name":null,"role":"exhaust_component","typical_concentration":"varies by traffic volume and ventilation"}],"identifiers":{"common_names":["parking garage air quality (vehicle exhaust infiltration, pm2.5, no2, co)"],"aliases":[],"manufacturer":null,"brands":[]},"brand_examples":[{"brand":"Carrier","manufacturer":"Carrier Global","market_position":"professional","notable":"Leading HVAC manufacturer"},{"brand":"Trane","manufacturer":"Trane Technologies","market_position":"professional","notable":"Commercial HVAC systems"},{"brand":"Honeywell","manufacturer":"Honeywell","market_position":"mass_market","notable":"HVAC controls and air quality"}],"brand_examples_disclaimer":"Representative branded products of this category. Concerning ingredients listed in materials.concerning[] apply to the category, not necessarily to every named brand. Specific formulations vary by SKU and may have changed since this record was written; consult the brand's current ingredient label before drawing brand-level conclusions.","sources":[{"type":"expert_curation","name":"ALETHEIA Safety Database","date":"2026-03-25"},{"type":"regulation","title":"IBC/IMC Parking Garage Ventilation + OSHA CO PEL (IBC 406; IMC 403.3; ASHRAE 62.1-2022; 29 CFR 1910.1000)","jurisdiction":"USA","citation":"IBC 406; IMC 403.3; ASHRAE 62.1-2022; 29 CFR 1910.1000","id":"src_4fef5350"},{"id":"iarc_100f","type":"regulatory","title":"IARC Monographs Volume 100F: Benzene","year":2012,"inherited_from_compound":"hq-c-org-000010"},{"id":"epa_benzene_iris","type":"regulatory","title":"US EPA IRIS Assessment: Benzene","year":1998,"inherited_from_compound":"hq-c-org-000010"}],"meta":{"schema_version":"4.0.0","last_updated":"2026-03-25","timestamp":"2026-05-14T01:22:39.547Z"}}