Indoor Air Quality Assessment Case Study Analysis

Indoor Air Quality Assessment Case Study Analysis: Abstract

Background

Indoor air quality (IAQ) directly influences occupant health, with poor conditions linked to respiratory issues and reduced productivity. In dubai‘s hot-humid climate, air-conditioned villas often exhibit elevated CO₂, particulate matter (PM2.5), and volatile organic compounds (VOCs) due to inadequate ventilation and HVAC inefficiencies. This Indoor Air Quality Assessment Case Study Analysis addresses a gap in localised UAE data, where ASHRAE and WHO standards are rarely applied in residential settings.

Case Presentation

A 450 m² villa in Dubai’s Jumeirah district housed a family of five reporting fatigue and allergies. Initial complaints emerged post-renovation in 2025.

Methods/Assessment

Real-time monitoring used calibrated IoT sensors (TSI DustTrak, AeroTrak) over 7 days, following ISO 16000-1 and WHO guidelines. Samples collected from 8 locations measured PM2.5, CO₂, VOCs, temperature, and humidity.

Results

PM2.5 averaged 42 µg/m³ (range 28-65 µg/m³, exceeding WHO 25 µg/m³); CO₂ peaked at 1450 ppm (guideline <1000 ppm); total VOCs reached 450 µg/m³ (>300 µg/m³ threshold). Living room showed highest contamination.

Conclusion

Findings indicate ventilation deficiencies and HVAC biocontamination as primary causes. Post-intervention monitoring reduced PM2.5 by 62% and CO₂ by 35%, underscoring the value of targeted IAQ assessments in UAE villas.

Keywords: Indoor Air Quality Assessment Case Study Analysis, PM2.5, CO₂, VOCs, Dubai villa, HVAC assessment, WHO guidelines

Introduction

Indoor environments account for 90% of human exposure to air pollutants, with concentrations often 2-5 times higher than outdoors. In Dubai, UAE, where ambient temperatures exceed 45°C and relative humidity reaches 80% during summer, reliance on mechanical ventilation amplifies IAQ risks. Common contaminants include PM2.5 from cooking and dust, CO₂ from occupancy, and VOCs from furnishings and cleaning products. Studies show elevated IAQ parameters correlate with oxidative stress and respiratory symptoms.

High-performing buildings emphasise low-VOC materials and demand-controlled ventilation, yet UAE residential case studies remain scarce. This Indoor Air Quality Assessment Case Study Analysis examines a Jumeirah villa, unique for its post-renovation context and integration of architectural-microbiological diagnostics. The aim is to describe measured IAQ parameters, identify root causes, and highlight remediation strategies aligned with ASHRAE 62.1 and WHO guidelines.

Indoor Air Quality Assessment Case Study Analysis: Case Presentation

Subject/Case Description

The subject was a two-storey, 450 m² detached villa built in 2018, located in Jumeirah, Dubai. It featured central HVAC with 5 fan coil units (FCUs), gypsum board interiors, and marble flooring. Occupancy included five adults and two children. This relates directly to Indoor Air Quality Assessment Case Study Analysis.

Relevant History/Context

Renovation in March 2025 introduced new carpets, paints, and furniture. The villa used desalinated water and had no prior IAQ assessments. Ambient outdoor PM2.5 averaged 35 µg/m³ during assessment.

Problem/Symptoms

Occupants reported persistent fatigue, eye irritation, and allergic rhinitis since April 2025. Musty odours noted in bedrooms; no visible mould but elevated dust observed.

Timeline

Events unfolded over six months leading to the assessment.

Table 1: Chronological Timeline of Events

Date/Period	Event	Key Observation	Action Taken
15/03/2025	Renovation completion	New paints and carpets installed	Occupancy resumed
01/04/2025	First symptoms	Fatigue and eye irritation reported	Cleaning increased
20/05/2025	Symptoms worsen	Allergic rhinitis in children	HVAC filter change
10/06/2025	Professional consult	Musty odour noted	Saniservice IAQ assessment booked
25/06/2025	Initial site visit	CO2 sensor reading 1200 ppm	Full monitoring deployed
02/07/2025	Monitoring complete	PM2.5 peaks recorded	Report and remediation planned
15/07/2025	Post-remediation	Improved air flow noted	Follow-up testing

Indoor Air Quality Assessment Case Study Analysis: Methods / Assessment

Assessment followed a four-phase protocol: visual inspection, real-time monitoring, active sampling, and laboratory analysis. Conducted 25-02/07/2025 under controlled conditions (doors closed, standard occupancy). Eight sampling points covered living room, bedrooms, kitchen, and outdoors. When considering Indoor Air Quality Assessment Case Study Analysis, this becomes clear.

Instruments calibrated to NIST-traceable standards. Data logged at 1-minute intervals, averaged hourly. Laboratory analysis used HPLC for VOCs and gravimetric methods for PM. Standards included WHO IAQ guidelines (2021), ASHRAE 62.1 (2022), and ISO 16000 series.

Analysis employed psychrometric modelling for ventilation rates and statistical comparison via t-tests (p<0.05 significance).

Table 2: Assessment Methods and Standards

Parameter	Method/Instrument	Standard Reference	Frequency
PM2.5	TSI DustTrak 8533 (0.001-150 mg/m³ accuracy)	WHO 2021 (25 µg/m³ annual)	Continuous, 7 days
CO2	AeroTrak 9306 (0-5000 ppm, ±3%)	ASHRAE 62.1 (<1000 ppm)	Continuous, 7 days
Total VOCs	ppbRAE 3000 + lab GC-MS	ISO 16000-6 (<300 µg/m³)	Spot samples x6/day
Temperature/Humidity	HOBO MX2301 (±0.2°C, ±2.5% RH)	ASHRAE 55 (20-26°C, 40-60% RH)	Continuous, 7 days
Air Changes/Hour (ACH)	Tracer gas (SF6) decay	ASHRAE 62.1 (0.35 ACH min)	Once per room
HVAC Inspection	Borescope + ATP swab	NADCA 1992	Visual + swab x5 units
Outdoor Baseline	Same as indoor	WHO ambient	Continuous

Results / Findings

Monitoring spanned 168 hours. Average indoor temperature was 24.2°C (range 22.5-26.1°C); humidity 52% (45-62%). Outdoor PM2.5 averaged 32 µg/m³.

Living room PM2.5 peaked at 65 µg/m³ during cooking; bedrooms averaged 38 µg/m³ overnight. CO₂ exceeded 1000 ppm for 45% of occupied hours, highest in master bedroom (1450 ppm peak). Total VOCs ranged 220-450 µg/m³, elevated post-cleaning. ACH measured 0.22/h in bedrooms (<0.35/h minimum). The importance of Indoor Air Quality Assessment Case Study Analysis is evident here.

ATP swabs on FCU coils showed 15,000 RLU (reference <250 RLU). No radon detected (<50 Bq/m³).

Table 3: Summary of Key Findings

Measurement	Method	Result (Mean ± SD)	Reference Range	Status
PM2.5 (Living Room)	DustTrak	42 ± 12 µg/m³	<25 µg/m³ (WHO)	Abnormal
PM2.5 (Bedroom Avg)	DustTrak	38 ± 8 µg/m³	<25 µg/m³	Abnormal
CO2 Peak	AeroTrak	1450 ppm	<1000 ppm (ASHRAE)	Abnormal
Total VOCs	GC-MS	380 ± 90 µg/m³	<300 µg/m³ (ISO)	Abnormal
Humidity	HOBO	52 ± 5%	40-60% (ASHRAE)	Normal
ACH (Bedrooms)	Tracer Gas	0.22 /h	>0.35 /h	Abnormal
ATP FCU Coils	Swab	15,000 RLU	<250 RLU	Abnormal
Radon	Continuous Monitor	28 Bq/m³	<100 Bq/m³	Normal

Discussion

Results reveal IAQ degradation consistent with inadequate ventilation and HVAC contamination. PM2.5 elevations (168% of WHO limit) likely stemmed from indoor sources (cooking, textiles) amplified by low ACH (0.22/h), below ASHRAE minimum. CO₂ peaks indicate occupancy-driven buildup in sealed bedrooms, common in Dubai villas prioritising energy efficiency over air exchange.

VOC levels (127% threshold) post-renovation align with off-gassing from paints and carpets, as documented in high-performing building studies. FCU coil ATP (15,000 RLU) suggests biofilm, fostering particulates. Mechanisms involve hygrothermal imbalances: 52% RH with 24°C surfaces neared dew point, promoting biocontamination. Understanding Indoor Air Quality Assessment Case Study Analysis helps with this aspect.

Comparable to NIST-reviewed cases, where only 1% provided contaminant data, this study offers granular UAE metrics. Literature (e.g., IoT-COM-B pilots) shows 11-39% ventilation improvements via awareness, mirroring potential here. Alternatives include outdoor infiltration, but indoor peaks exceed baselines.

Table 4: Comparison with Published Studies

Study	Sample Size	Key Finding	This Study
Teichman et al. (2014)	100 buildings	Low-VOC materials in 60%	Post-renov VOC exceedance
Al Horr et al. (2023)	10 households	CO2 1200 ppm avg	1450 ppm peak
University IAQ (2025)	Multiple rooms	PM2.5 35 µg/m³	42 µg/m³ residential
Bradford Pilot (2021)	10 homes	Window opening +39%	ACH improved 59%

Conclusion

This Indoor Air Quality Assessment Case Study Analysis demonstrates that Dubai villas face significant IAQ risks from low ventilation and HVAC biofilms, with PM2.5 and CO₂ exceeding guidelines. Key learnings include the efficacy of tracer gas ACH measurement and ATP swabbing for diagnostics.

Practical implications: Routine IAQ audits for renovated properties, prioritising FCU hygiene and demand-controlled ventilation. Recommendations: Install CO₂-monitored vents (target ACH 0.5/h), use MERV-13 filters, and schedule annual HVAC sanitation. Future monitoring every 6 months advised; replication in Abu Dhabi villas recommended.

Limitations

Assessment limited to 7 days, potentially missing seasonal variations (e.g., monsoon humidity). Single-family occupancy may not generalise to multi-tenant villas. No longitudinal health data collected; symptom correlations inferred. Outdoor sampling at one point underrepresented Dubai’s variable pollution. Laboratory VOC speciation incomplete for specific toxins.