YielixREI & PHI Tracker — Restricted Entry Interval and Pre-Harvest Interval Calculator
Track your pesticide restricted entry intervals (REI) and pre-harvest intervals (PHI) with real-time countdown timers. Enter your application date and time along with the REI and PHI from the product label, and the calculator shows exactly when workers can safely re-enter the field and when the crop can be legally harvested. Stay compliant with EPA Worker Protection Standards.
Inputs Explained
- Application Date & Time
- The exact date and time of your pesticide application. Both REI and PHI countdowns start from this moment.
- REI (hours)
- The Restricted Entry Interval in hours, found on the product label under Agricultural Use Requirements. Typically ranges from 4 to 48 hours.
- PHI (days)
- The Pre-Harvest Interval in days, found on the product label under Directions for Use for your specific crop. Ranges from 0 to 60+ days.
- Product Name
- Optional label for your records. Helps track multiple applications across different fields or products.
How This Calculator Works
Worked Example
Applied a fungicide at 8:00 AM on March 15 with a 24-hour REI and 14-day PHI
- 1. Enter application details
Set date to March 15 and time to 08:00. Enter REI = 24 hours and PHI = 14 days.
- 2. REI clearance
The calculator adds 24 hours to 8:00 AM March 15, giving a re-entry time of 8:00 AM March 16.
- 3. PHI clearance
The calculator adds 14 days to March 15, giving an earliest harvest date of March 29.
- 4. Monitor status colors
Red = interval active (restricted). Amber = clearing soon. Green = interval expired (safe).
Workers can re-enter at 8:00 AM March 16. Crop can be harvested from March 29 onward.
How to Interpret Your Results
| Condition | What It Means |
|---|---|
| Red (Active) | The interval has not expired. The treated area is restricted for worker entry (REI) or the crop cannot be harvested (PHI). |
| Amber (Warning) | The interval is close to clearing — within 24 hours for REI or within 1 day for PHI. Prepare for the upcoming clearance. |
| Green (Cleared) | The interval has fully expired. The area is safe to enter (REI) or the crop is safe to harvest (PHI). Always verify against the product label. |
Common Mistakes to Avoid
Using the wrong REI or PHI from the label
REI is in the "Agricultural Use Requirements" section (in hours). PHI is in the "Directions for Use" section for your specific crop (in days). They are in different parts of the label.
Forgetting that REI and PHI run simultaneously
Both intervals start at the same time — the application moment. REI (hours) usually clears well before PHI (days). Both must be independently satisfied.
Not recording the exact application time
REI is measured in hours, so the exact time matters. A 12-hour REI applied at 6 PM clears at 6 AM — recording only the date loses this precision.
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Related Guides
Understanding Spray Application Rates
Learn how to read pesticide labels, calculate dilution rates, calibrate your sprayer, and determine the right product quantity for your field.
Restricted Entry and Pre-Harvest Intervals Explained
Understand REI and PHI requirements, why they matter for worker safety and food safety, and how to track compliance.