Climate change presents an existential threat to public health and a direct challenge to the delivery of healthcare services in the UK. The NHS, which contributes 4% of the UK's carbon footprint , is responding with a world-leading commitment to become the first net-zero national health service, an ambition enshrined in the Health and Care Act (2022). For Emergency Departments (EDs), this national mandate coincides with the compounding crisis of rising demand, creating both a significant challenge and a unique opportunity.The Royal College of Emergency Medicine (RCEM) has established the GreenED initiative to guide departments in this transition. This briefing synthesises the core principles and practical guidance for implementing environmentally sustainable practices within the emergency care setting.

Key Takeaways:

• Sustainability as Quality Improvement: The core principle is that sustainable healthcare is high-quality healthcare. By improving efficiency, optimising patient pathways, and reducing waste, EDs can enhance patient care, improve staff well-being, generate cost savings, and reduce their environmental impact simultaneously.

• Leadership is Crucial: A key finding from the GreenED pilot project is that lasting change is exceptionally difficult without senior buy-in. Engaging clinical leads, senior nurses, and managers by aligning green initiatives with trust-level strategic goals (e.g., cost savings, patient experience) is essential for success.

• A Whole-Team Approach: Effective change requires the engagement of all staff, from consultants and nurses to porters, administrative staff, and managers. Establishing a multidisciplinary "Green ED" group is a foundational first step.

• The "Reduce, Reuse, Recycle" Hierarchy: The greatest environmental and financial benefits come from reducing consumption in the first place (e.g., rationalising blood tests, avoiding unnecessary cannulation). This is a more impactful strategy than reuse, which in turn is more effective than recycling.

• Actionable Framework: This document provides a practical framework covering strategic context, RCEM's official recommendations, and a detailed guide to implementation, including forming a green group, identifying carbon hotspots, and motivating an already exhausted workforce with tangible, data-driven benefits.