PowerPoint ® Presentation Chapter 15 Troubleshooting and Mitigating IAQ Problems Troubleshooting and Mitigating IAQ Problems Overview of Non-IAQ Problems Indoor Air Quality Control Strategies Judging Proposed Mitigation Designs and Their Success Sample Case Study Problems and Solutions

PowerPoint ® Presentation Chapter 15 Troubleshooting and Mitigating IAQ Problems Troubleshooting and Mitigating IAQ Problems Overview of Non-IAQ Problems Indoor Air Quality Control Strategies Judging Proposed Mitigation Designs and Their Success Sample Case Study Problems and Solutions

Chapter 15–Troubleshooting and Mitigating IAQ Problems All indoor air quality complaints must be handled using the procedures established by a building or company.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Water entering an occupied space will cause damage to materials and cause mold and mildew to grow at a rate that is dependent on the humidity levels in the space.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Airflow pathways can change with changes in furniture location and modifications to space layout. Pollutant pathway records indicate the normal airflow paths through spaces of a building for future reference.

Chapter 15–Troubleshooting and Mitigating IAQ Problems To accept that an IAQ problem has been solved, all requirements should be met: the HVAC system operates as designed, no contaminant sources that were found remain, and the occupant complaints about a space have stopped.

Chapter 15–Troubleshooting and Mitigating IAQ Problems To reduce eyestrain, glare can be reduced by changing the computer monitors background colors, using antiglare screens, increasing the frequency of breaks, and reducing the normal lighting levels in computer spaces to the 30 fc to 50 fc range.

Chapter 15–Troubleshooting and Mitigating IAQ Problems The available options when dealing with a strong contaminant source are to seal or cover the source, or remove or reduce the source.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Sealing a space can be a difficult technique to implement because of hidden airflow pathways above drop ceilings and against brick or block walls, but space sealing has other benefits such as energy savings and pest control.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Diluting contaminants by increasing the flow of outdoor air to meet ASHRAE Standard , Ventilation for Acceptable Indoor Air Quality causes an energy increase of less than 5% in most commercial buildings.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Temperature stratification typically occurs in building spaces with high ceilings in which ceiling-mounted supply diffusers distribute the heated air.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Properly designed and installed local exhaust results in far lower contaminant levels in a building than could be accomplished by a general increase in dilution ventilation.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Air cleaning removes contaminants from the air. Particulate filtration, electrostatic precipitation, and negative ion generators are designed to remove particulates, while gas sorption is designed to remove gases.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Because ozone is harmful at elevated levels, standards and guidelines have been established for ozone in indoor air. The amount of ozone emitted from electrostatic precipitators varies from model to model.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Because specialized knowledge, skills, and instrumentation are needed to evaluate lighting, noise, vibration, ergonomic stress, and psychosocial stress, such evaluations should be performed by a qualified individual in that field.

Chapter 15–Troubleshooting and Mitigating IAQ Problems When a local exhaust system is being used, the system must be strong enough and close enough to the contaminant source so that none of the contaminant is drawn into nearby return grills and recirculated back into the HVAC system.

Chapter 15–Troubleshooting and Mitigating IAQ Problems Reduced occupant complaints and good air measurement readings are used to judge the success of an investigation and mitigation effort to correct an indoor air problem.