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The Public Right-of-Way Accessibility Guidelines (PROWAG) rulemaking has concluded. The PROWAG final rule has been published in the Federal Register. Please visit the Access Board’s PROWAG page for the guidelines.

Indoor Environmental Quality

Appendix 1—Site Selection: Potential Sources for Pollutants and EMF.

The Committee recognizes that few, if any, building sites are likely to be free of all the pollutant sources listed below. The recommendation is to minimize proximity to as many of these sources as possible in order to maximize outdoor environmental quality and hence indoor environmental quality.

Table A-1 Potential Sources of Pollutants and EMF

General (Air, Soil) Engine Exhaust Pesticides Industrial / Commercial EMF
  • Recognized area of poor air quality
  • Smog
  • Smoke (chimney, industrial, etc.)
  • Superfund Sites
  • Brownfields
  • Landfills
  • Hazardous waste sites
  • Compost sites
  • Underground storage tanks
  • Floodplains
  • Wetlands
  • Filled-in wetlands
  • Military bases
  • Heavy traffic
  • Highways
  • Interstates
  • Diesel exhaust
  • Airports
  • Agriculture (unless organic)
  • Golf courses
  • Mosquito spraying
  • Parks & Forests
  • Roadside spraying
  • Dairies
  • Chicken & hog farms
  • Other intensive livestock operations
  • Refineries
  • Mines
  • Chemical plants
  • Cement plants
  • Power plants
  • Manufacturing
  • Logging/Pulp mills
  • Incinerators
  • Sewage treatment plants
  • Gas stations
  • Dry cleaners
  • Other commercial sources that emit air pollutants (See Appendix 5 on Use & Occupancy)
  • Substations
  • Cell phone towers
  • Radio towers
  • Transponders
  • Transformers
  • High tension lines
  • Electrical distribution lines
  • Radar installations
  • Military bases
  • Airports
  • Electrical Transportation
  • Power-generating dams

Appendix 2—Roof Gardens

Roof gardens involve a range of potential issues related to moisture penetration and mold growth. Flat roofs are prone to pooling water and leaking. Foot traffic can cause or accelerate deterioration leading to leaking. Roof repair is more difficult under gardens. Plants may attract pests that subsequently encourage pesticide use. Planting soils can create dust. Plants can emit volatile fumes and pollen. Plants can drop leaves and fruit that rot and become moldy. Selected plants should be low allergen plants without strong fragrance (See Exterior Landscaping above). If used, roof gardens should be located away from air intakes, operable windows, and doors. Design should ensure that moisture will not penetrate the roof membrane or cause conditions of standing water.

Appendix 3—Pest Prevention

Exterior Design

Remove lights on or near building that may attract night-flying insects.

Maintain a plant-free zone of about 12 inches around buildings to discourage insects from entering.

Design weep-holes in window frames to prevent access by paper wasps. Design windows to prevent harborage and access for pests, without clear passageways to inside.

Correct structural features that provide opportunities for bird roosting and nesting. Avoid locating decorative lattices over entrances to food services facilities that may inadvertently serve as bird roosts.

Install bird-proof barriers that are designed to prevent both pigeon and sparrow access to preferred nesting sites.

Design exterior light fixtures so that birds cannot roost or nest on or in them. Fit eave roof tiles with bird stops (that will also exclude bats, bees and wasps).

Correct structural features that provide opportunities for rodent harborage and burrowing.

Screen or otherwise eliminate animal access under decks, porches, stairways. Seal porches and ramps to the building foundation with ¼inch hardware cloth screen mesh to form a barrier to digging pests such as rats and skunks. This screen must extend 12 inches into the ground and must have a right-angled, 6 inches wide, outward extending shelf to prevent burrowing under the screen.

Screen ventilation louvers with ¼inch hardware cloth screen mesh to exclude birds, rodents, cats, etc., (coordinate with mechanical requirements).

Maintain a 2-foot pea gravel strip around buildings to prevent rodent burrowing. Use a 3” layer of sand barrier underneath slab construction. Use 1–3 mm particle size in place of unsifted sand to provide a permanent sand barrier to termites (both western subterranean and Formosan termites). This will prevent termites from penetrating cracks in slab construction.

For wood not in contact with the ground or concrete, use wood pre-soaked in disodium octoborate tetrahydrate.

Refuse and Recycling Areas

Place outdoor garbage containers, dumpsters, and compactors on hard, cleanable surfaces and away from building entrances (at least 50 feet from doorways). Design site with properly graded concrete or asphalt pads to help prevent rats from establishing burrows beneath them.

Design site with solid enclosure that extends all the way to the ground. Use metal or synthetic materials, as opposed to chain-link, wood, etc. to prevent rodents from gnawing and climbing the enclosure.

Design trash storage areas that can be closed off from the rest of the building.

Locate storage areas for boxes, paper supplies, and other materials in areas separate from where food or trash is stored. When stored together, these materials put food and shelter together, attracting pests.

Landscaped Areas

Choose proven performers, plants known to do well in the intended planting area. Avoid plants with history of pest problems. Use resistant plant species and cultivars when available. Check with your university or cooperative extension service for recommendations.

Give preference to plants that shed a minimum of seeds and fruits, that may attract and support insects, rodents, and undesired birds.

Design with diversity. Include a wide variety of plants in the landscape to reduce the pest damage potential.

Provide a properly prepared site. Site selection is critical; the site must be compatible with the plants’ requirements.

Design landscaped areas with flexibility to allow for campus additions, which may change drainage, exposure to sunlight, ventilation, or other plant requirements.

Avoid crowding of landscape plantings.

Group plantings with similar cultural requirements.

Install or retrofit fence lines and other turf or landscape borders with concrete mowing strips.

Avoid planting vegetation directly against buildings as this provides shelter and sheltered runways for rodents. For the same reason, avoid planting dense vegetation that completely covers the ground.

Do not plant vines which climb building walls, as these create runways for rodents and harborage for undesired bird species.

Plant trees away from buildings to prevent easy access to buildings for insects and rodents.

Give careful consideration to placement of deciduous trees. Leaves which accumulate along foundations provide harborage and sheltered runways for rodents.


Food Preparation and Serving Areas (main kitchen, dining room, teachers’ lounge, snack area, vending machines, and food storage rooms):

  • Ensure that new kitchen appliances and fixtures are of pest-resistant design, i.e., open design, few or no hiding places for roaches, freestanding and on casters for easy, thorough cleaning.
  • Provide space under and around appliances and equipment in kitchen areas to allow maximum ventilation and ease of (steam) cleaning.
  • Use coving at floor-to-wall junctures to minimize build-up of debris and to facilitate cleaning.
  • Slope floors in kitchen areas to provide good drainage after cleaning.
  • Do not install pegboard in kitchens, animal rooms, or laboratories.
  • Insure that all pipe insulation has a smooth surface and that there are no gaps between pieces.
  • Refrigerate trash/recycling storage rooms.

Classrooms and Offices

Ensure that new office and classroom furniture that is rarely moved (e.g., staff desks, bookcases, filing cabinets) is designed to permit complete cleaning under and around the furniture, or to allow ready movement for cleaning purposes.

Design or retrofit construction to provide adequate ventilation, preventing trapped moisture and condensation.

Storage Areas

Equip area with self-closing doors.

Building Perimeter

Seal all plumbing and electrical service entrances.

Keep doors closed tightly; equip doors with self-closures and door sweeps.

Appendix 4—Carpet

Stone, terra cotta, granite, marble, terrazzo, ceramic, brick, or sealed concrete flooring is best tolerated by individuals with chemical sensitivities. Wood flooring that has not been recently stripped or refinished is also often well tolerated by people with chemical sensitivities.

Carpet systems contain a myriad of chemicals in their fiber, dyes, backing, padding, bonding agents, adhesives, antimicrobials, flame retardants, and stain resistance, anti-static, and color fast agents. They also are reservoirs for tracked-in pesticides, dust, dust mites; foster mold growth; and absorb and remit volatile organic chemicals like fragrances and paint fumes. In addition, many solvent-based agents used to clean carpets emit toxic fumes.

The Carpet and Rug Institute (CRI) has established a rating system and testing program (Green Label Plus) that may be used in lieu of the emissions testing criteria of California’s Collaborative for High Performance School (CHPS) Section 01350 (See Products & Materials Committee).

Some people with chemical sensitivities have found that carpet squares with self-adhesive backing have been the best tolerated new carpeting. Others have reacted adversely to such products. More research is necessary to determine what factors in these carpets and/or which brands are best tolerated.

Older carpets are usually better tolerated by people with chemical sensitivities than new ones, as long as they have not become moldy.

Recommendations regarding carpeting (design, materials, and O&M issues)

  • Minimize the use of carpeting.
  • Use areas rugs in place of carpeting whenever possible.
  • Consider using self-adhesive carpet squares.
  • Tack rather than glue down (unless using self-adhesive carpet).
  • If glue down, use low or no VOC adhesive.
  • Air out carpet for at least two weeks prior to installation.
  • Exceed building flush-out of two weeks if possible.
  • Reduce the need for and the frequency of carpet replacement through good maintenance (e.g., thorough vacuuming and frequent cleaning with low toxic products and procedures—See recommendations by O&M).
  • Minimize amount of carpet that is replaced, limit replacement to damaged areas. (A major advantage of carpet square systems is that smaller sections can be replaced).

Appendix 5—Use and Occupancy

Non industrial businesses/activities that may generate chemical pollutants include, but are not limited to:

  • Hair and Nail Salons
  • Spas
  • Restaurants
  • Grills & BBQ
  • Furniture stores
  • Woodworking and crafts shops
  • Art/Pottery studios
  • Auto Parts
  • Taverns/Bars
  • Tobacco Shops
  • Tattoo Parlors
  • Dry Cleaners
  • Laundromats
  • Nurseries (Plants)
  • Landscaping, Pest Control
  • Florists
  • Candle/Soap/bath shops
  • Pet Shops
  • Photo/Printing/Copy shops
  • Specialty foods stores
  • Leather goods stores
  • Perfume shops or departments
  • Labs (eyeglasses, medical, etc.)
  • Dental offices
  • Dialysis Centers

Areas that should be vented directly to the outside include: kitchens, labs, computer rooms, copy/fax areas, printer or blueprint rooms, storage areas for toxic materials, showers, locker rooms, and areas where animals are present.

Appendix 6—Landscaping

Use low allergen plants (see Ogren Plant Allergy Scale).

Plant female trees and shrubs (they do not produce pollen).

Avoid the use of plants that have strong fragrances, such as jasmine, lavender, peppermint, and roses.

Avoid or minimize lawn/turf areas to reduce mowing emissions and chemical usage.

Use low growing fine fescue, buffalo grass, or other turf grass which requires little or no mowing.

Use a wide variety of plant materials.

Group plants with similar water and cultural needs.

Do not crowd plants.

Leave gaps in groundcover to create less hospitable habitat for pests.

Plant deciduous shade trees on the south and west sides of buildings. The shade reduces interior temperatures and reduces A/C usage during summer months.

Use low or no VOC paints, stains and finishes on outside equipment including benches, poles, decks, and other outdoor equipment. (see recommendations from Building Products & Materials group)

Avoid organic mulches (cocoa beans, peat moss, bark, wood chips) as they emit volatile fumes and may harbor mold.

Avoid railroad ties as they contain creosote.

Utilize stone, clay, concrete, and other hard, non-volatile materials to create borders and frame gardens.