Indoor Air Quality (IAQ) is a complex issue involving relationships among factors such as building design, usage, operating conditions, occupancy, furnishings, equipment, and layout. Thus, an initial investigation designed to characterize factors that affect a building’s air quality must be broad based rather than specific. The building and surrounding potential sources should be inspected and observed before any air testing and laboratory analysis are conducted.
An IAQ evaluation should include defining and characterizing the current status of factors that affect air quality. The following 13 items and related questions should be considered:
1. The building itself
- What type of construction is it (for example, steel, masonry, glass, brick)?
- How many floors does it have?
- What is its proximity to traffic? Are in-house parking facilities available?
- Is the surrounding area residential, commercial, or industrial?
2. Building design vs. usage
- Does the original tenant (or tenants) still occupy the building?
- Was the building originally designed to be used by one or more tenants?
- Do the tenants still conduct the same types of business?
3. Building occupants
- What is the occupant density?
- Are there large differences in occupancy loading from floor to floor or zone to zone?
4. Occupant/tenant activities
- What types of businesses are conducted?
- Is the usage residential, commercial, light manufacturing, or a combination of office and industrial?
- Are there special-use rooms, cafeterias, break rooms, et cetera?
- Is smoking permitted? If so, is a separately ventilated smoking lounge available?
- Is the nature of the business inherently stressful?
5. Building ventilation system
- Is there a mechanical means of ventilation, or does the building rely on infiltration?
- If the building has a mechanical air-handling system, what were the original HVAC design specifications?
- Do current as-built drawings exist?
- Are testing and balancing records on file?
- What type of air-handling system is in place (for example, variable air volume, constant volume)?
- What is the energy source (for example, gas, oil, electricity)?
- Are the air-handling zones defined?
- Does the mechanical HVAC system have ventilation capabilities? If so, where are the outdoor air intakes?
- Are the air intakes likely to be affected by such pollution sources as building exhaust, automobile/diesel emissions, cooling tower spray, standing water, or exhaust/fumes from neighboring businesses and/or industries?
- Are the outdoor air dampers in good working order?
- Is there a minimum setting to ensure a continuous supply of outdoor air to the building?
- What is the condition of such components of the air-handling unit as the coils, filters, condensate pans, insulation, and sound lining?
6. Building maintenance
- Is a written O&M program in place and up to date?
- Is there a good record-keeping procedure to track the filter changes/cleaning, balancing data, coil cleaning, and other maintenance procedures?
7. Interior layout
- What is the layout of the office space (for example, open floor areas, partitioned interior or exterior offices, modular office cubicles)?
- Do partitioned offices have both a supply diffuser and a return grille?
- How high are the modular dividers, and are they flush with the floor?
- Has the interior layout been changed since the air-handling system was installed?
- Is there good airflow in the space? Can the airflow pathways be characterized (ventilation smoke tubes should suffice)?
8. Furnishings
- Do the floors have carpet, tile, wood, or other materials?
- Does the office contain wood or pressed wood products or window treatments?
- Does the space have upholstered furniture and modular partitions?
9. Office equipment
- How many dry-process and wet-process photocopying machines are available?
- Are the copy machines in separately vented rooms?
- Where are the copier chemicals stored?
- Is the office space crowded with computer terminals, computer printers, laser printers, and fax machines?
- Is there paper-shredding activity or considerable handling of carbonless paper?
10. Outdoor air quality
- Are such items as industrial emission sources, water treatment plants, and landfills nearby?
- What is the predominant wind direction?
- Are there cyclical, predictable traffic flow patterns that could affect the air quality?
- Is construction activity ongoing in the vicinity of the building?
11. Housekeeping procedures
- Is there a written record of housekeeping procedures and a file of housekeeping chemical compounds?
- Where are the cleaning materials stored?
- Do employees eat at their workstations, and is there an in-place procedure regarding the storage of food in break-room refrigerators?
- Is there a log of pesticide use?
12. Ongoing remodeling/renovation
- Are procedures in place to prevent renovation and remodeling activities from adversely affecting the building air supply?
- Are MSDSs for such materials as cleaners, adhesives, and paints on file?
13. Accidents
- Has there been a plumbing mishap, a leaking roof, or water damage to carpeting, furnishings, air-handling ductwork, or duct insulation?
- Has there been a spill of cleaning compounds or stored office chemicals?
- Has there been a fire (electrical or otherwise)?
- Have chemicals been released into the ground?
Evaluating the Information
Evaluating the information gathered during the IAQ inspection accomplishes several objectives, including the following:
- It enables the IAQ investigator to get a handle on the building systems and operations.
- It allows the IAQ investigator to recommend to owners and managers procedural and management modifications designed to avert building air-quality problems.
- It provides a focus for implementing a ventilation study and an air-quality sampling strategy designed to evaluate air quality.
- It helps to establish baseline building conditions, which are essential as control conditions for maintenance in the absence of specific complaints or problems.
This article is adapted from two of BOMI International’s course: Environmental Health and Safety Issues. More information regarding this course is available by calling 1-800-235-2664. Visit BOMI International’s Web site.
