The abbreviations on this page were originally defined on the United States Environmental Protection Agency website.

I/A: Innovative/Alternative

IA: Interagency Agreement

IAAC: Interagency Assessment Advisory Committee

IADN: Integrated Atmospheric Deposition Network

IAG: Interagency Agreement

IAP: Incentive Awards Program. Indoor Air Pollution

IAQ: Indoor Air Quality

IARC: International Agency for Research on Cancer

IATDB: Interim Air Toxics Data Base

IBSIN: Innovations in Building Sustainable Industries

IBT: Industrial Biotest Laboratory

IC: Internal Combustion

ICAIR: Interdisciplinary Planning and Information Research

ICAP: Inductively Coupled Argon Plasma

ICB: Information Collection Budget

ICBN: International Commission on the Biological Effects of Noise

ICCP: International Climate Change Partnership

ICE: Industrial Combustion Emissions Model. Internal Combustion Engine

ICP: Inductively Coupled Plasma

ICR: Information Collection Request

ICRE: Ignitability, Corrosivity, Reactivity, Extraction

ICRP: International Commission on Radiological Protection

ICRU: International Commission of Radiological Units and Measurements

ICS: Incident Command System. Institute for Chemical Studies; Intermittent Control Strategies.; Intermittent Control System

ICWM: Institute for Chemical Waste Management

IDEA: Integrated Data for Enforcement Analysis

IDLH: Immediately Dangerous to Life and Health

IEB: International Environment Bureau

IEMP: Integrated Environmental Management Project

IES: Institute for Environmental Studies

IFB: Invitation for Bid

IFCAM: Industrial Fuel Choice Analysis Model

IFCS: International Forum on Chemical Safety

IFIS: Industry File Information System

IFMS: Integrated Financial Management System

IFPP: Industrial Fugitive Process Particulate

IGCC: Integrated Gasification Combined Cycle

IGCI: Industrial Gas Cleaning Institute

IIS: Inflationary Impact Statement

IINERT: In-Place Inactivation and Natural Restoration Technologies

IJC: International Joint Commission (on Great Lakes)

I/M: Inspection/Maintenance

IMM: Intersection Midblock Model

IMPACT: Integrated Model of Plumes and Atmosphere in Complex Terrain

IMPROVE: Interagency Monitoring of Protected Visual Environment

INPUFF: Gaussian Puff Dispersion Model

INT: Intermittent

IOB: Iron Ore Beneficiation

IOU: Input/Output Unit

IPCS: International Program on Chemical Safety

IP: Inhalable Particles

IPM: Inhalable Particulate Matter. Integrated Pest Management

IPP: Implementation Planning Program. Integrated Plotting Package; Inter-media Priority Pollutant (document); Independent Power Producer

IPCC: Intergovernmental Panel on Climate Change

IPM: Integrated Pest Management

IRG: Interagency Review Group

IRLG: Interagency Regulatory Liaison Group (Composed of EPA, CPSC, FDA, and OSHA)

IRIS: Instructional Resources Information System. Integrated Risk Information System

IRM: Intermediate Remedial Measures

IRMC: Inter-Regulatory Risk Management Council

IRP: Installation Restoration Program

IRPTC: International Register of Potentially Toxic Chemicals

IRR: Institute of Resource Recovery

IRS: International Referral Systems

IS: Interim Status

ISAM: Indexed Sequential File Access Method

ISC: Industrial Source Complex

ISCL: Interim Status Compliance Letter

ISCLT: Industrial Source Complex Long Term Model

ISCST: Industrial Source Complex Short Term Model

ISD: Interim Status Document

ISE: Ion-specific electrode

ISMAP: Indirect Source Model for Air Pollution

ISO: International Organization for Standardization

ISPF: (IBM) Interactive System Productivity Facility

ISS: Interim Status Standards

ITC:Innovative Technology Council

ITC: Interagency Testing Committee

ITRC: Interstate Technology Regulatory Coordination

ITRD: Innovative Treatment Remediation Demonstration

IUP: Intended Use Plan

IUR: Inventory Update Rule

IWC: In-Stream Waste Concentration

IWS: Ionizing Wet Scrubber