Re-Entry Intervals (REI)
Legally required waiting period before people can re-enter treated areas without PPE - protecting occupants from pesticide exposure.
Detailed Overview
REI is minimum time people must stay out of treated areas to prevent exposure. Label specifies REI: typically 0-24 hours depending on product and application. Until REI expires, only applicators wearing PPE can enter. Common REIs: Many crack-and-crevice and spot treatments: REI until spray dries (typically 2-4 hours). Some products: 4 hours, 12 hours, or 24 hours regardless of drying. Outdoor applications: may specify REI until spray settles and dries. Agricultural products: longer REIs (48-72 hours) but rarely used in structural pest control. Legal requirements: (1) Post warning signs if required by label. (2) Inform occupants of REI. (3) Prevent entry during REI. (4) Do not allow unprotected entry before REI expires. Violations: allowing occupants to return before REI expires is serious violation risking illness and legal consequences. Practical concerns: scheduling treatments when occupants can vacate for REI, communicating REI to customers clearly, ensuring compliance in multi-unit buildings where neighbors may enter areas unknowingly. Short REI products preferred for occupied spaces. No-REI (dries = safe) products ideal for sensitive accounts. Document that you communicated REI to customer.
When to Use
Check label REI for every product. Communicate REI to customer before treatment. Post signs if required. Ensure occupants stay out until REI expires. Schedule treatments when buildings can be vacated if needed.
Required Skill Level
Should only be performed by licensed pest management professionals
Benefits
- Protects occupants from pesticide exposure
- Legal requirement - prevents violations
- Reduces liability from exposure incidents
- Demonstrates safety consciousness
- Specified on label for every product
Limitations
- Long REIs inconvenient for customers
- Difficult to enforce in multi-unit buildings
- Customers may ignore instructions and re-enter early
- Limits treatment options in some situations
Related Concepts
Other principles that may be useful
Integrated Pest Management (IPM)
A prevention-based pest management method that provides long-lasting pest control, improves building conditions, and is less harmful to residents and pets than traditional pest control.
Pest Triangle
The four essential requirements pests need to survive: food, water, shelter, and ways to get around. Eliminating any of these makes an environment inhospitable to pests.
Threshold Levels
The point at which pest populations or damage reaches a level that requires action. IPM uses threshold levels to determine when treatment is necessary rather than treating on a schedule.