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Documentation for the Waste Reduction Model (WARM)

Documentation for the Waste Reduction Model (WARM) includes user guides, detailed chapters on the development of the greenhouse gas (GHG), energy and economic factors used in WARM as well as several background supporting documents.

On this page:

Documentation for GHG Emission, Energy and Economic Factors Used in WARM

The WARM documentation explains the calculation of emission factors by material type, or group of materials, arranged into individual chapters. EPA also provides chapters addressing each specific materials management practice that is available in WARM, along with a background and overview chapter, a list of definitions and acronyms, user’s guides for the different versions of the WARM tool, a summary of recent updates in WARM and additional chapters on special topics like forest carbon sequestration, energy factors and economic impacts.

The WARM documentation chapters are grouped into several files based on the following chapter topics:

  • User's Guide WARM Version 15: provides an overview for users who may be new to the tool or need some basic knowledge about downloading and modeling scenarios in WARM version 15

  • User’s Guide WARM version 15 Excel: provides an overview for users of the Excel-based tool for WARM version 15. This guide is the same as the guide found on the first sheet of the WARM Excel tool

  • Background includes chapters covering:

    • WARM Background and Overview
    • Definitions and Acronyms
    • Recent Updates in WARM
    • Forest Carbon Storage
  • Management Practices includes chapters covering:

    • Source Reduction
    • Recycling
    • Anaerobic Digestion
    • Composting
    • Combustion
    • Landfilling
    • Energy Impacts
    • Economic Impacts
  • Containers, Packaging and Non-Durable Goods Materials includes chapters covering:

    • Glass
    • Metals
    • Paper Products
    • Plastics
    • Polylactide (PLA) Biopolymer
  • Organic Materials includes chapters covering:

    • Food Waste
    • Yard Trimmings
  • Electronics chapter

  • Tires chapter
  • Construction Materials includes chapters covering:

    • Asphalt Concrete
    • Asphalt Shingles
    • Carpet
    • Clay Bricks
    • Concrete
    • Drywall
    • Fiberglass Insulation
    • Fly Ash
    • Vinyl Flooring
    • Wood Flooring
    • Wood Products

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Additional Resources for WARM - User Guidance and Landfilling Factors

In addition to the WARM documentation chapters, EPA has compiled several documents that provide additional information on using WARM and the emission, energy and economic factors applied in WARM. These additional documents are grouped by topic, including:

  • User Guidance on How to Use Materials and Management Pathways Not Found in WARM: This user guidance provides information on ways to use materials or management pathways not found in WARM, including WARM emission, energy and economic factors; modeling food donation benefits; modeling increased product lifetime; modeling reuse; and the differences between WARM’s life-cycle greenhouse gas (GHG) accounting approach and GHG emission inventories.

  • Landfilling and Landfill Carbon Storage: This document provides more detailed information on how landfilling and landfill carbon storage are modeled in WARM.

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