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Oregon Commercial Pesticide Applicators Exam
QUESTIONS AND DETAILED SOLUTIONS JUST
RELEASED
Oregon Commercial Pesticide Applicators Exam
Point-Form Exam Coverage (Based on ODA Core Manual – 2024)
Based on the Oregon Department of Agriculture (ODA) Pesticide Applicator Licensing Program, the exam
covers the following core domains :
1. LAWS & REGULATIONS (25-30%)
• Oregon Revised Statutes (ORS) Chapter 634 – Pesticide Control
• Oregon Administrative Rules (OAR) 603-057 – Pesticide Use
• Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
• Worker Protection Standard (WPS) – 40 CFR Part 170
• Oregon specific rules: licensing categories, reporting requirements, drift rules
• Recordkeeping: 3 years for restricted-use pesticides; 2 years for general use (commercial)
• Pesticide dealer licensing requirements
• Civil penalties up to $10,000 per violation (ORS 634.990)
2. PESTICIDE LABELING (15-20%)
• Label vs. labeling (label includes all written material attached to container)
• Signal words: Danger-Poison (skull & crossbones, ≥500 mg/kg oral LD50), Danger, Warning,
Caution
• Restricted Use Pesticide (RUP) designation
• Personal Protective Equipment (PPE) requirements listed on label
• Re-entry intervals (REI) – WPS requires 4-hour minimum for most, up to 30+ days for some
• Pre-harvest intervals (PHI) for agricultural crops
3. SAFETY & TOXICOLOGY (15-20%)
• Acute toxicity vs. chronic toxicity
• Routes of exposure: dermal (most common), inhalation (most dangerous), oral
• LD50 (lethal dose for 50% of test animals) – lower number = higher toxicity
• Cholinesterase inhibitors: organophosphates and carbamates
• PPE levels: A, B, C, D
• Heat stress prevention in PPE
• First aid for pesticide poisoning: call Poison Control (1-800-222-1222)
4. ENVIRONMENTAL FATE (10-15%)
• Volatility: vapor pressure (higher = more volatile)
• Solubility: water solubility affects runoff and leaching
• Persistence: half-life in soil
• Adsorption: binds to soil organic matter
• Microbial degradation, photodegradation, hydrolysis
• Drift management: droplet size, temperature inversion (most hazardous for drift)
• Endangered Species Protection Bulletins
5. EQUIPMENT & CALIBRATION (10-15%)
• Calibration frequency: each season, when changing products, when conditions change
• Nozzle types: flat fan (broadcast), cone (airblast), flood (liquid fertilizer)
• Pressure affects droplet size: higher pressure = smaller droplets (more drift)
• Cleaning equipment after use – triple rinse before disposal
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• Anti-backflow devices (check valves) to prevent contamination
• Maintenance of PPE
6. APPLICATION METHODS (8-10%)
• Banded vs. broadcast application
• Directed spray vs. broadcast
• Soil incorporation
• Chemigation – requires anti-backflow device
• Aerial application regulations (OAR 603-057-0130)
• Basal bark, cut stump, injection for forestry and right-of-way
7. IPM & PEST BIOLOGY (5-8%)
• Integrated Pest Management (IPM): economic threshold, action threshold
• Pest identification: weed, insect, disease
• Life cycles affect timing of control
• Resistant pest management – rotating modes of action (FRAC, HRAC, IRAC codes)
• Biological, cultural, mechanical, chemical controls
8. TRANSPORTATION & STORAGE (5%)
• Secure transport of pesticides – separated from food/feed
• Storage: locked, dry, ventilated, secondary containment required for >55 gallons or >500 pounds
dry
• Spill containment and reporting: Oregon requires reportable quantity spills to ODA and DEQ
Question 1
A commercial applicator is applying a restricted-use pesticide on a Christmas tree farm in Clackamas
County. How long must the application record be retained under Oregon law?
A) 1 year
B) 2 years
C) 3 years
D) 5 years
Answer: C
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*ORS 634.246 requires commercial applicators to retain restricted-use pesticide application records for
3 years; general-use records must be kept for 2 years.*
Question 2
A pesticide label contains the signal word "DANGER" with a skull and crossbones symbol. What oral
LD50 range does this represent for a rat?
A) >2,000 mg/kg
B) 500-2,000 mg/kg
C) 50-500 mg/kg
D) <50 mg/kg
Answer: D
*"Danger-Poison" with skull and crossbones indicates Category I toxicity, oral LD50 <50 mg/kg (highly
toxic).*
Question 3
A worker enters a treated greenhouse 2 hours after a pesticide application that has a 4-hour restricted-
entry interval (REI). What is the violation?
A) No violation if the worker wears PPE
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B) The REI was not observed; worker must wait full 4 hours
C) Only if the pesticide is a restricted use product
D) No violation if the greenhouse is well ventilated
Answer: B
WPS requires all workers to stay out of treated areas for the full REI specified on the label; early entry is
only allowed for specific early-entry workers with PPE.
Question 4
During calibration of a boom sprayer, the applicator increases the pressure from 30 psi to 60 psi. How
does this affect droplet size?
A) Droplets become larger
B) Droplets become smaller, increasing drift potential
C) Droplet size is unaffected by pressure
D) Droplets become larger only with flat-fan nozzles
Answer: B
Higher pressure forces liquid through the nozzle orifice faster, shearing into smaller droplets, which
increases drift risk. Lower pressure produces larger, less drift-prone droplets.
Oregon Commercial Pesticide Applicators Exam
QUESTIONS AND DETAILED SOLUTIONS JUST
RELEASED
Oregon Commercial Pesticide Applicators Exam
Point-Form Exam Coverage (Based on ODA Core Manual – 2024)
Based on the Oregon Department of Agriculture (ODA) Pesticide Applicator Licensing Program, the exam
covers the following core domains :
1. LAWS & REGULATIONS (25-30%)
• Oregon Revised Statutes (ORS) Chapter 634 – Pesticide Control
• Oregon Administrative Rules (OAR) 603-057 – Pesticide Use
• Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
• Worker Protection Standard (WPS) – 40 CFR Part 170
• Oregon specific rules: licensing categories, reporting requirements, drift rules
• Recordkeeping: 3 years for restricted-use pesticides; 2 years for general use (commercial)
• Pesticide dealer licensing requirements
• Civil penalties up to $10,000 per violation (ORS 634.990)
2. PESTICIDE LABELING (15-20%)
• Label vs. labeling (label includes all written material attached to container)
• Signal words: Danger-Poison (skull & crossbones, ≥500 mg/kg oral LD50), Danger, Warning,
Caution
• Restricted Use Pesticide (RUP) designation
• Personal Protective Equipment (PPE) requirements listed on label
• Re-entry intervals (REI) – WPS requires 4-hour minimum for most, up to 30+ days for some
• Pre-harvest intervals (PHI) for agricultural crops
3. SAFETY & TOXICOLOGY (15-20%)
• Acute toxicity vs. chronic toxicity
• Routes of exposure: dermal (most common), inhalation (most dangerous), oral
• LD50 (lethal dose for 50% of test animals) – lower number = higher toxicity
• Cholinesterase inhibitors: organophosphates and carbamates
• PPE levels: A, B, C, D
• Heat stress prevention in PPE
• First aid for pesticide poisoning: call Poison Control (1-800-222-1222)
4. ENVIRONMENTAL FATE (10-15%)
• Volatility: vapor pressure (higher = more volatile)
• Solubility: water solubility affects runoff and leaching
• Persistence: half-life in soil
• Adsorption: binds to soil organic matter
• Microbial degradation, photodegradation, hydrolysis
• Drift management: droplet size, temperature inversion (most hazardous for drift)
• Endangered Species Protection Bulletins
5. EQUIPMENT & CALIBRATION (10-15%)
• Calibration frequency: each season, when changing products, when conditions change
• Nozzle types: flat fan (broadcast), cone (airblast), flood (liquid fertilizer)
• Pressure affects droplet size: higher pressure = smaller droplets (more drift)
• Cleaning equipment after use – triple rinse before disposal
, Page 2 of 155
• Anti-backflow devices (check valves) to prevent contamination
• Maintenance of PPE
6. APPLICATION METHODS (8-10%)
• Banded vs. broadcast application
• Directed spray vs. broadcast
• Soil incorporation
• Chemigation – requires anti-backflow device
• Aerial application regulations (OAR 603-057-0130)
• Basal bark, cut stump, injection for forestry and right-of-way
7. IPM & PEST BIOLOGY (5-8%)
• Integrated Pest Management (IPM): economic threshold, action threshold
• Pest identification: weed, insect, disease
• Life cycles affect timing of control
• Resistant pest management – rotating modes of action (FRAC, HRAC, IRAC codes)
• Biological, cultural, mechanical, chemical controls
8. TRANSPORTATION & STORAGE (5%)
• Secure transport of pesticides – separated from food/feed
• Storage: locked, dry, ventilated, secondary containment required for >55 gallons or >500 pounds
dry
• Spill containment and reporting: Oregon requires reportable quantity spills to ODA and DEQ
Question 1
A commercial applicator is applying a restricted-use pesticide on a Christmas tree farm in Clackamas
County. How long must the application record be retained under Oregon law?
A) 1 year
B) 2 years
C) 3 years
D) 5 years
Answer: C
, Page 3 of 155
*ORS 634.246 requires commercial applicators to retain restricted-use pesticide application records for
3 years; general-use records must be kept for 2 years.*
Question 2
A pesticide label contains the signal word "DANGER" with a skull and crossbones symbol. What oral
LD50 range does this represent for a rat?
A) >2,000 mg/kg
B) 500-2,000 mg/kg
C) 50-500 mg/kg
D) <50 mg/kg
Answer: D
*"Danger-Poison" with skull and crossbones indicates Category I toxicity, oral LD50 <50 mg/kg (highly
toxic).*
Question 3
A worker enters a treated greenhouse 2 hours after a pesticide application that has a 4-hour restricted-
entry interval (REI). What is the violation?
A) No violation if the worker wears PPE
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B) The REI was not observed; worker must wait full 4 hours
C) Only if the pesticide is a restricted use product
D) No violation if the greenhouse is well ventilated
Answer: B
WPS requires all workers to stay out of treated areas for the full REI specified on the label; early entry is
only allowed for specific early-entry workers with PPE.
Question 4
During calibration of a boom sprayer, the applicator increases the pressure from 30 psi to 60 psi. How
does this affect droplet size?
A) Droplets become larger
B) Droplets become smaller, increasing drift potential
C) Droplet size is unaffected by pressure
D) Droplets become larger only with flat-fan nozzles
Answer: B
Higher pressure forces liquid through the nozzle orifice faster, shearing into smaller droplets, which
increases drift risk. Lower pressure produces larger, less drift-prone droplets.
