CONTAM User Guide and Program Documentation Version 3.2

Abstract

This manual describes the computer program CONTAM version 3.2, developed by NIST. CONTAM is a multizone indoor air quality and ventilation analysis program designed to help determine airflows, contaminant concentrations, and personal exposure in buildings. Airflows include infiltration, exfiltration, and room-to-room airflow rates and pressure differences in building systems, and can be driven by mechanical means, wind pressures acting on the exterior of the building, and buoyancy effects induced by temperature differences between zones, including the outdoors. Contaminant concentrations include the transport and fate of airborne contaminants, due to airflow, chemical and radio-chemical transformation, adsorption and desorption to building materials, filtration, and deposition to and resuspension from building surfaces. Personal exposure includes the exposure of building occupants to airborne contaminants, for eventual risk assessment.CONTAM can be useful in a variety of applications. Its ability to calculate building airflow rates and relative pressures between zones of the building is useful for assessing the adequacy of ventilation rates in a building, for determining the variation in ventilation rates over time, for determining the distribution of ventilation air within a building, for estimating the impact of envelope air-tightening efforts on infiltration rates, and for evaluating the energy impacts of building airflows. The program has also been used extensively for the design and analysis of smoke management systems. The prediction of contaminant concentrations can be used to determine the indoor air quality performance of buildings before they are constructed and occupied, to investigate the impacts of various design decisions related to ventilation system design and building material selection, to evaluate indoor air quality control technologies, and to assess the indoor air quality performance of existing buildings. Predicted contaminant concentrations can also be used to estimate personal exposure based on occupancy patterns. Version 2.0 contained several new features including: non-trace contaminants, practically unlimited number of contaminants, contaminant-related libraries, separate weather and ambient contaminant files, building controls, scheduled zone temperatures, improved solver to reduce simulation times and several user interface related features to improve usability. Version 2.1 introduced more new features including the ability to account for spatially varying external contaminants and wind pressures at the building envelope, more new control elements, particlespecific contaminant properties, total mass released calculations and detailed program documentation. Version 2.4 introduced two new deposition sink models, a one-dimensional convection/diffusion contaminant model for ducts and user-selectable zones, new contaminant filter models, control super nodes, super filters, a duct balancing tool, building pressurization and model validity tests and several other usability enhanceme...

A Comparative Study of Indoor Radon Levels between Two Similar Dwellings Using CONTAM Software

“…The software used is CONTAM version 3.2 [7], developed by NIST, the first version being released in [13,14]. In the present study, it was used mainly to model natural and mechanical airflow and to determine the radon concentrations based on predefined indoor sources.…”

“…This paper reports a comparative study of indoor radon level in two similar dwellings based on simulation performed with the multizone modeling software CONTAM, version 3.2, developed by the National Institute of Standards and Technology (NIST) [7]. In a previous paper [8], a radon measurement campaign was carried out in both dwellings, located in the same building.…”

Resolving Stack Effect Problems in a High-Rise Office Building by Mechanical Pressurization

“…The total volume of the building is about 500,000 m 3 . The passenger elevator shafts are designed for three separate vertical zones: the low-rise zone elevators serve Measurements of pressure differences (ΔPs) across the elevator doors were conducted on selected floors between the first and 60th floors: Floors 1,4,8,12,16,20,25,29,33, 37, 41, 45, 48, 52 and 56. During the measurements, the outdoor and indoor air temperatures were, respectively, −5.2 °C and 22 °C, and the outdoor wind velocity was less than 1 m/s at a height of 16 m from the ground level, which means that external wind pressure on the building was negligible.…”

“…The computer program used in this study was CONTAM [25], developed by the National Institute of Standards and Technology (NIST) in the United States. Figure 5 shows CONTAM models for the first floor and a typical floor (50th floor) serviced by the high-rise elevator shaft.…”

Development of CPSC nano-particle modeling tools

“…Occupant exposure to airborne nanoparticles can be characterized by indoor airflow and contaminant transport analysis software. The U.S. National Institute of Standards and Technology (NIST) has been developing CONTAM for many years [3], which is the most widely used software of this type. As such, the U.S. Consumer Product Safety Commission (CPSC) is working with NIST to develop modeling tools to enable evaluation of consumer exposure to airborne ENPs in the built environment.…”