Re-Entry Interval & When It's Safe To Go Back In
Protects workers
Enter the spray date and the label's REI hours to get the safe re-entry date— when workers can go back into the treated field without protective equipment, away from harmful residues.
Re-entry interval (REI)
Next: keep workers out of the sprayed field until Jun 3, 2026; if anyone must enter sooner, they need the label-specified PPE.
The REI is set on the product label and may differ for early-entry tasks; always follow the actual label and local regulations.
Re-entry interval — key facts
- Re-entry date
- spray date/time + REI hours
- Common REIs
- 4, 12, 24, 48, 72 hours
- Source
- the pesticide label
- During REI
- no entry without PPE
- Why
- fresh residues are harmful
- Hand tasks
- may need a longer REI
- Also check
- the pre-harvest interval (PHI)
- Privacy
- Runs in your browser; nothing uploaded
Keep crews out until the residues have settled
After a field is sprayed, the residues on leaves, soil and equipment are at their strongest. Sending workers back in too soon — to scout, weed, thin or harvest — exposes them to chemicals that can be absorbed through skin, inhaled or swallowed. The re-entry interval on the label sets the minimum wait that gives those residues time to dry, bind and break down to safer levels, which is why it is a legal requirement, not a suggestion.
This tool turns the spray date and the label's REI hours into a clear safe re-entry date and the number of full days to wait. Use it to plan field work, brief crews, and post the re-entry time on the gate. Pair it with the Pre-Harvest Interval, Spray Schedule and Sprayer Tank Cleanout calculators for a complete crop-protection routine.
Protect workers
Keep crews out until residues are safe.
Stay compliant
Meet the label's restricted entry rule.
Plan field work
Know the exact day work can resume.
Post the gate
Show a clear, dated re-entry time.
Frequently Asked Questions
What is a re-entry interval (REI)?+
The re-entry interval, also called the restricted entry interval, is the time that must pass after a pesticide is applied before workers may go back into the treated field without personal protective equipment. It is set on the product label and protects people from harmful residues on foliage, soil and surfaces while they are still strong.
How is the safe re-entry date calculated?+
Add the REI hours from the label to the date and time of application. Safe re-entry = spray date/time + REI hours. For example a 12-hour REI on a spray finished at 8 am means re-entry is safe from 8 pm the same day; a 48-hour REI means two full days later.
Where do I find the REI for my product?+
The REI is printed on the pesticide label, usually in the Agricultural Use Requirements or worker-protection box. Common values are 4, 12, 24, 48 or 72 hours, and some products differ by crop or task. Always use the label for the exact product and rate you applied — it is the legal source.
Can anyone enter the field during the REI?+
Generally no one should enter without correct personal protective equipment during the restricted entry interval. Limited exceptions exist in some worker-protection rules (for short, essential tasks with PPE and training), but the safe rule for routine work is to wait until the REI has fully elapsed.
Why does re-entry matter for worker safety?+
Fresh pesticide residues on leaves and soil can be absorbed through skin, inhaled or transferred to the mouth, causing acute poisoning and longer-term harm. The REI gives residues time to dry, bind and break down to safer levels, which is why re-entering early without protection is a real health risk.
Does rain or weather change the REI?+
The labelled REI is the legal minimum and does not shorten with weather. Rain, heat or wind can change how fast residues break down, but you must still observe at least the full label REI. When in doubt, wait longer rather than less, and follow any extra local rules.
What if a product has more than one REI?+
Some labels list different re-entry intervals by crop, application method or activity (for example a longer REI for hand tasks like thinning or harvesting). Use the longest interval that applies to the task workers will do, so everyone re-enters safely.
How does this differ from the pre-harvest interval?+
The re-entry interval protects people working in the field; the pre-harvest interval (PHI) protects consumers by setting how long before harvest you may spray. They are separate label requirements with different lengths — meet both. See the Pre-Harvest Interval calculator for the PHI side.
Are these figures exact?+
The re-entry date is exact arithmetic from the date you enter and the label REI hours. The accuracy depends on recording the true application finish time and using the correct REI for your product and task. Always treat the label as the authority and keep a spray record.