Environment of Care
Domain 7 - Environment of Care
This domain tests the physical environment as a transmission risk: construction, ventilation, water systems, and surface management.
Core rules
- Construction/renovation requires a pre-project infection control risk assessment (ICRA) classifying the activity and the patient risk group. Higher classes mean impermeable barriers, negative-pressure containment with HEPA filtration, sealed doors and vents, designated debris routes, and daily documented monitoring.
- Ventilation: airborne infection isolation rooms ≥12 air changes per hour and negative pressure relative to the corridor, verified daily; protective environments for high-risk patients (e.g., allogeneic HSCT) use HEPA filtration and positive pressure.
- Water: a water management program per ASHRAE Standard 188 to control Legionella - temperature control, flushing infrequently used fixtures, monitoring, and remediation for high-risk units. Pseudomonas and nontuberculous mycobacteria also originate in water.
- Routine environmental culturing is not recommended; sample only as part of a targeted investigation.
- Clean high-touch surfaces frequently; assign responsibility between nursing and environmental services; manage linen, waste, and food safely; prohibit decorative fountains and restrict plants in high-risk areas.
Worked example
Renovation on the floor above an oncology unit. Reasoning: high-risk patients with demolition nearby likely warrant the highest ICRA class - hard barriers, HEPA units exhausting outside the work area, negative pressure inside the barrier, sealed penetrations, dedicated debris transport, and daily inspection. Environmental sampling is not indicated unless cases appear.
Traps
Assuming the HVAC system alone prevents transmission; failing to reassess the ICRA when project scope changes; placing an AIIR in a room whose pressure cannot be monitored; allowing sinks to be used for disposal of body fluids or medications (biofilm and splash risk).