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Indoor Semi-volatile Organic Compounds (i-SVOC) Version 1.0

What is i-SVOC?

i-SVOC Version 1.0 is a general-purpose software application for dynamic modeling of the emission, transport, sorption, and distribution of semi-volatile organic compounds (SVOCs) in indoor environments. i-SVOC supports a variety of uses, including exposure assessment and the evaluation of mitigation options.

SVOCs are a diverse group of organic chemicals that can be found in:

  • Pesticides; 
  • Ingredients in cleaning agents and personal care products;
  • Additives to vinyl flooring, furniture, clothing, cookware, food packaging, and electronics.

Many are also present in indoor air, where they tend to bind to interior surfaces and particulate matter (dust).

Who should use i-SVOC?

i-SVOC is intended for advanced users who have experience with indoor environmental quality modeling and exposure assessment.

What are the benefits of using i-SVOC?

Understanding the presence and distribution of SVOCs in buildings is critical to estimating exposures through: 

  • inhalation of air and suspended particulate matter;
  • skin contact with contaminated surfaces and dust; and
  • incidental ingestion of dust.

i-SVOC allows users to estimate the SVOC distributions in indoor environments with multiple sources and sinks. It can be: 

  • applied to exposure models that inform risk assessment and management decisions;
  • used to evaluate the effectiveness of pollution remediation methods, such as variable ventilation rates, source removal, and source encapsulation;  
  • provide a platform where users can build and experiment with their own models; and
  • reduce the uncertainties in multimedia models for SVOCs in indoor environments.  

How does i-SVOC work?

i-SVOC is an indoor exposure and environmental assessment software application that can address multiple diffusional sources and sinks in a single simulation. The program supports dynamic modeling of SVOC interactions with suspended and settled particles, which can be size-segregated. Additionally there are multiple options for the simulation output, such as concentrations in indoor media and mass fluxes.

System Requirements

i-SVOC runs on personal computers with Microsoft Windows XP, 7, or 8. It is a stand-alone application that does not require third-party software. It has not been tested for use on Apple operating systems.

Relevant Publications

User's Guide (PDF 92 pp, 1.4 MB)

Technical Contact

Xiaoyu Liu (