The Central Pollution Control Board (CPCB) on January 22, 2025, issued Report on Classification of Sectors into Red, Orange, Green, White and Blue Categories (A tool for progressive environmental management)-2025.
The Central Pollution Control Board (CPCB) introduced the Pollution Index (PI) scoring methodology in 2016 to create a standardized approach for assessing the environmental impact of industrial sectors. This methodology evaluates factors like water pollution, air pollution, and hazardous waste generation to determine how harmful an industry is to the environment.
Based on the PI score, CPCB classified industries into four categories:
Red (63 sectors): Highly polluting industries that require stringent regulatory measures and continuous monitoring.
Orange (91 sectors): Moderately polluting industries that need to follow regulations but may not require as intensive monitoring as Red sectors.
Green (65 sectors): Least polluting industries, considered environmentally friendly, with fewer regulatory requirements.
White (38 sectors): "Practically non-polluting" industries, which are exempt from the regulatory requirements because their environmental impact is minimal.
The White category was particularly notable as it recognized sectors that had a very low or negligible environmental impact. Furthermore, the responsibility for categorizing new or leftover sectors was delegated to State Pollution Control Boards (SPCBs) and Pollution Control Committees (PCCs), which could use the CPCB’s methodology to evaluate these industries.
This classification system helps streamline the regulatory process, ensuring that industries are monitored and regulated based on their specific environmental impact.
The CPCB revised the methodology for calculating the Pollution Index (PI) and classifying sectors into Red, Orange, Green, and White categories based on pollution levels. After receiving about 700 comments on the draft, the methodology was finalized, focusing on three key pollutant groups:
• Water Pollutant Score (PIW): Assesses water pollution based on wastewater’s oxygen demand, pollutants present, and volume generated.
• Air Pollutant Score (PIA): Evaluates air pollution from process emissions, work zone emissions (fugitive and odor), and fuel type/quantity used.
• Waste Pollutant Score (PIH): Considers the type and amount of hazardous, toxic, infectious, or bulk waste produced.
This revised methodology helps classify sectors based on their environmental impact for better regulation and management.
The salient features of the revised classification methodology:
• Methodology focusses on “Potential to pollute the environment” by the sector.
• Simplified single formula for Cumulative Pollution Index for all cases.
• Equal weightage to all three pollutant groups- Air, Water, and Waste.
• Cumulative PI based on weighted proportionate scores of pollutant groups.
• Separate scoring criteria for sectors generating sewage (such as Building & construction projects, STPs, Airports, etc.) and bio-medical waste (Health Care Facilities).
• Introduced Blue Category for 9 sectors under Essential Environmental Services required for management of waste generated from domestic/household activities.
• Appropriate weightage to scale of operations by introducing more slabs to bifurcates sub-sectors based on pollution load, scale of operation, production technology and type of fuel used.
• Introduction of sub-categories for sectors based on cleaner technologies, fuel types, integrated/segregated operations etc.
• Motivation to industries for progressive environmental management.
• A tool to assess the Cumulative Pollution Index and category based on the revised method.
This report outlines a revised approach for classifying industrial sectors based on their pollution potential. The new classification system categorizes sectors into red, orange, green, white, and blue, to improve environmental management and regulatory oversight. It discusses the origin of this classification system, the necessity for updating the 2016 methodology, and the scoring system used to calculate the cumulative Pollution Index (PI).
For further information, please refer to the document below.
