Does Good Indoor Air Quality Really Improve Workplace Productivity?

FMP and Property Event – 29 & 30 April 2014

Ammar Al-ShemeryAssociate Director of the Abu Dhabi CampusHead of Operations and Campus Services

Contents

• Why the need for good indoor air?

• HVAC Systems

• Productivity in the Workplace

• Case Study

Why the need for good indoor air?Estimated that inefficient buildings cost British business £135bn per year in lost opportunity (Glensler, 2005)

1-2% improvement in productivity has a larger economic return than 100% saving in energy costs” (CIBSE1999)

Indoor air pollution is the 8th most important in the range of risk factors in the global burden of disease and responsible for 2.7% of it (WHO, 2005)

50% of all illnesses are either caused or aggravated by polluted indoor air. (The American College of Allergy, Asthma and Immunology, ACAAI, 2009)

The total annual cost of poor IAQ to U.S. employers is $15 billion due to worker inefficiency and sick leave (OSHA, 2008)

(Bartlett, 2006)

Definition of Indoor Air Quality?

The environmental characteristics inside buildings that may affect human health, comfort, or work performance. IAQ characteristics include the concentrations of amounts of pollutants in indoor air, as well as air temperature and humidity.(Lawrence Berkeley National Laboratory, 2011)

Air within a building occupied for at least one hour by people of varying states of health. This can include the office, classroom, transport facility, shopping centre, hospital and home. National Health and Medical Research Council of Australia (NHMRC)

Major Source of Contaminants Contaminants Major Source

Particles Dust (generated inside and outside), smoking, cooking

Allergens (a substance that can cause an allergic reaction)

Molds, pets, many other resources

Bacteria and viruses People, moisture, petsCarbon dioxide (CO2) Occupants breathing, combustionOdoriferous chemicals People, cooking, molds, chemicals, smokingVolatile Organic Compound (VOC)

Construction materials, furnishings, cleaning products

Tobacco smoke SmokingCarbon monoxide (CO) Incomplete and/or faulty combustion, smokingRadon (Rn) Radioactive decay of radium in the soilFormaldehyde (HCHO) Construction materials, furniture, smokingOxides of Nitrogen Combustion, smokingSulfur dioxide CombustionOzone Photocopiers, electrostatic air cleaners

McDowall, 2007

HVAC SystemsObjectives of the HVAC system

To control:

1)Air temperature

2)Humidity

3)Air circulation

4)Air quality(ASHRAE, 2004)

Energy Analysis and Comfort Solutions Inc., 2006

Achieving Efficiency

HVAC Selection Parameters

Commissioning of HVAC System

HVAC Maintenance and Cleaning

National Air Duct Cleaning Association, NADCA , 2005

Building Use

Classification

Air

Handling

Unit

Supply

Ductwork

Return

Ductwork/Exhaust

Industrial 1 year 1 year 1 year

Residential 1 year 2 years 2 years

Light Commercial 1 year 2 years 2 years

Commercial 1 year 2 years 2 years

Healthcare 1 year 1 year 1 year

Marine 1 year 2 years 2 years

HVAC Cleanliness Inspection Schedule

HVAC Systems

Productivity in the Workplace

Factors Influencing Comfort(McDowall, 2007)

Factors Affecting Workplace Productivity(Hedge, 2004)17%

Measuring Productivity

McCartney & Humphreys (2002)

Lorsch and Abdou (1994)

Wyon (1996)

A- Simulated work

B- Diagnostic tests

C- Embedded tasks

D- Absenteeism records

E- Self-assessment

F- Use of existing measures

D- Absenteeism records

Productivity in the Workplace

CASE STUDYThe Facility

MethodologyCASE STUDY

Improvement Measures

HVAC System Assessment

CASE STUDY

PPM Programme

Sr. # Item Parameter Satisfied

Parameter not Satisfied

1 Filters and air cleaning devices

2 Outdoor air dampers and actuators

3 Humidifiers

4 Dehumidification coils

5 Drain pans and other adjacent surfaces subject to wetting

6 Outdoor air intake louvers, bird screens, mist eliminators and adjacent areas

7 Sensors used for dynamic minimum outdoor air control

8 Air handling systems except for units under 2000 cfm

9 Cooling towers

10 Floor drains located in plenums or rooms that serve as air plenums

11 Equipment component accessibility

12 Visible microbial contamination

13 Water intrusion or accumulation

Total 8 5

Percentage 61.5% 38.5%

Minimum Maintenance Activity and Frequency

CASE STUDY

Comfort Conditions CASE STUDY

Parameter Condition Satisfied

Condition not Satisfied

Basic Thermal Comfort    

• Consider humidity, air velocity, radiation  

• Consider occupant clothing and metabolic rate  

• Use ASHRAE Thermal Comfort Tool (ASHRAE 1997) or equivalent to select indoor design

 

• Design for part-load conditions  

• Select thermostat locations carefully  

• Educate occupants regarding clothing adaptation  

Zoning and Occupant Control    

• Use separate zone for each unique microenvironment  

• Educate occupants about thermostat settings and HVAC operation  

• Expand comfort envelope using personal cooling/ventilation  

• Expand comfort by occupant control over natural conditioning  

• Use operator control in case of “thermostat wars”  

Thermal Radiation    

• Use radiation (hot or cool) to expand the thermal comfort envelope  

• Shade excessive solar radiation  

Air Movement    

• Achieve the minimum velocity   

• Expand the upper thermal limits using air movement  

• Address drafts by selection of diffusers and heat location  

Part-Load Control    

• Maintain air velocity  

• Control humidity  

Operation Capabilities    

• Design to allow flexibility that can retain satisfaction levels  

• Adjustable set points allow response to occupant expectations  

HVAC System Checklist for Comfort Conditions

Facility Cleanliness CASE STUDY

High VOC

Indoor Air Quality InvestigationCASE STUDY

On-Site Improvements

Changing cleaning material and detergents to green materials that are more environmental friendly.

Adjusting air dampers for better ventilation rates

Adjusting VCDs (volume control dampers) towards better air movement.

Installing a temporary fan near the 9th floor corridor door to balance air pressure.

Placing lockable plastic covers on thermostat controls

Implementing “Zone Operating Schedule”

Sealing window gaps to avoid infiltration and enhance building envelope.

CASE STUDY

Indoor Air Quality TestCASE STUDY

Direct Instrumental Method of Analysis

8 hours

Survey QuestionnaireCASE STUDY

Survey Question(s) Air Quality Parameter

(HAAD Standard)

Effects Source

3 - PM10 and TSP The lower region of the respiratory tract.

Dust

4 & 5 - Air temperature

- Relative

humidity

Thermal comfort HVAC system

6

- Yeast and

mould

Sensitive people to allergenic reactions.

HVAC system, high humidity, reduced ventilation and HVAC system condensation.

- Formaldehyde Causes watery eyes, burning sensations in the eyes and throat, nausea, and difficulty in breathing.

Carpet glue, insulation material, furniture.

- Co Reduces the oxygen supply to the body causing suffocation.

Vehicles exhaust entry to the building.

- Co2 Thermal comfort Ventilation rate (HVAC system)

7 - VOC Eye, nose, and throat irritation; headaches, loss of coordination and central nervous system

Paint, cleaning material, adhesive, cosmetics and carpets

8 - TSP & PM2.5 Respiratory system Cigarette smoke

9 - General perception of air chemicals’ effects on general health

Various external and internal pollution sources

10, 11, 12, 13 & 14 High level of concentration for most parameters

Sick building syndrome (SBS)

Ventilation, poor HVAC system causing contamination.

Absenteeism RecordsCASE STUDY

Cause of absence that is related only to respiratory, allergy, headache…etc problems was taken into consideration

ResultsCASE STUDY

IAQ Test & Survey QuestionnaireParameter Averaging

Time

HAAD

Limit

Unit Detection

Limit

Results

Min. Max. Ave.

Air Temperature 8 hours Summer

24.5 ± 1.5˚C

- - 25.2 26.4 25.8

Relative humidity 8 hours 30 – 60 - - 38.1 42.5 40.3

Particulate

matters (PM2.5)

8 hours 0.025 mg/m³ 0.001 0.001 0.003 0.002

Particulate

matters (PM10)

8 hours - mg/m³ 0.001 0.002 0.002 0.002

Total suspended

particles (TSP)

8 hours - mg/m³ 0.001 0.002 0.004 0.003

Formaldehyde 8 hours 0.1 mg/m³ 0.01 0.013 0.03 0.021

Carbon dioxide 8 hours 1,000 ppm 1 488 580 534

Carbon monoxide 8 hours 9 ppm 0.001 0.533 0.0 0.72

Ozone 8 hours 0.1 ppm 0.01 < 0.01 < 0.01 < 0.01

Volatile organic

compound

(VOC)

8 hours 100 ppb 10 153 245 199

Total bacterial

count (TBC)

8 hours ≤ 1000 cfu/m³ - 356

Yeast and mould 8 hours ≤ 1000 cfu/m³ - 490

HAAD Standard (2009) Occupational and Indoor Air Quality, Health Authority Abu Dhabi, UAE

ResultsCASE STUDY

Conclusion

36%

Savings over 1 year upon implementing improvement measures

1000 £

CASE STUDY

The Pathway Ahead

1a)HVAC System technical issues

b)Facility Cleanliness Considerations

c)Indoor Air Quality Investigation

d)Indoor Air Quality Test

e)Survey Questionnaire

f)Interviews

2On-site improvements

3Indoor air quality test

4Absenteeism records

SO…..

Does Good Indoor Air Quality Really Improve Workplace Productivity?

THANK YOU FOR YOUR ATTENTION…