REHS/RS EXAM REAL QUESTIONS + DETAILED ANSWERS - LATEST
VERSION - TOP RATED (2026/2027)
Registered Environmental Health Specialist / Registered Sanitarian
2026 Trainee & Registered Level Exam Pack
Q1 What is the temperature danger zone for food?
ANS 40°F to 140°F (4°C to 60°C). Bacteria multiply rapidly within this
range and food should not remain in this zone for more than 2
hours (1 hour if ambient temp >90°F).
Q2 What is the minimum internal cooking temperature for
poultry?
ANS 165°F (74°C) for all poultry, including whole birds, ground poultry,
and stuffing.
Q3 Define HACCP and its purpose.
ANS Hazard Analysis and Critical Control Points (HACCP) is a
systematic preventive approach to food safety that identifies
physical, chemical, and biological hazards in production
processes. It is designed to prevent hazards rather than inspect
finished products.
Q4 What are the 7 HACCP principles?
ANS 1) Conduct hazard analysis, 2) Identify Critical Control Points
(CCPs), 3) Establish critical limits, 4) Establish monitoring
procedures, 5) Establish corrective actions, 6) Establish
, verification procedures, 7) Establish record-keeping and
documentation.
Q5 What is a Critical Control Point (CCP)?
ANS A step in the food production process where control can be
applied to prevent, eliminate, or reduce a food safety hazard to an
acceptable level.
Q6 What is the minimum cooking temperature for ground beef?
ANS 155°F (68°C) held for 15 seconds. This temperature destroys E.
coli O157:H7 and Salmonella.
Q7 What does 'FIFO' stand for in food storage?
ANS First In, First Out. This inventory management principle ensures
older stock is used before newer stock, reducing spoilage and
ensuring freshness.
Q8 What is the proper storage order from top to bottom in a
walk-in refrigerator?
ANS Top: Ready-to-eat foods. Below that: Seafood. Then: Whole cuts
of beef/pork. Then: Ground meats/fish. Bottom: Poultry (highest
cooking temp required).
Q9 What temperature must hot food be held at to prevent
bacterial growth?
ANS 140°F (60°C) or above. Hot holding equipment must maintain this
temperature throughout service.
Q10 What temperature must cold food be held at?
ANS 41°F (5°C) or below. This slows but does not eliminate bacterial
growth.
,Q11 What is the 2-hour/4-hour rule in food safety?
ANS Food in the danger zone 0–2 hours: can be used or refrigerated.
2–4 hours: must be used immediately. Over 4 hours: must be
discarded.
Q12 What are the Big 9 food allergens recognized by the FDA?
ANS Milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soybeans,
and sesame (added in 2023 under FASTER Act).
Q13 What is cross-contamination in food safety?
ANS The transfer of harmful microorganisms from one food, surface, or
person to another. This can be direct (raw meat touching ready-to-
eat food) or indirect (through shared equipment or hands).
Q14 What is the proper method for cooling cooked food?
ANS Cool from 135°F to 70°F within 2 hours, then from 70°F to 41°F
within an additional 4 hours (6 hours total). Methods: ice baths,
blast chillers, shallow pans.
Q15 What does pH measure and why is it important in food
safety?
ANS pH measures the acidity or alkalinity of food on a scale of 0–14.
Bacteria grow best between pH 4.6–7.5. Low pH (acid) inhibits
most pathogens; foods with pH below 4.6 are considered non-
PHF.
Q16 What is a Potentially Hazardous Food (PHF)?
ANS A food that supports bacterial growth: moist, protein-rich, and
neutral pH. Examples: meat, poultry, fish, dairy, cooked starchy
foods, cut melons, cooked legumes.
Q17 Define water activity (Aw) and its significance.
, ANS Aw is the measure of free water available for microbial growth (0–
1.0). Most bacteria require Aw ≥0.85. Foods with Aw <0.85 are
generally safe from bacterial spoilage.
Q18 What is Clostridium botulinum and how is it prevented?
ANS An anaerobic bacterium producing the most potent toxin known. It
thrives in low-acid, oxygen-free environments (canned goods).
Prevention: proper canning (pressure cooking), maintaining pH
<4.6, or Aw <0.93.
Q19 What are foodborne illness outbreak criteria?
ANS An outbreak is defined as two or more people experiencing similar
illness after eating the same food, confirmed by epidemiological
investigation. A single case of botulism or chemical poisoning may
also constitute an outbreak.
Q20 What is Norovirus and how is it transmitted?
ANS A highly contagious viral pathogen causing vomiting and diarrhea.
Transmitted via fecal-oral route, contaminated food/water, or
surfaces. One of the leading causes of foodborne illness in the
US.
Q21 What is the minimum cooking temperature for fish?
ANS 145°F (63°C) for 15 seconds. Parasitic destruction may require
specific time-temperature combinations or freezing protocols.
Q22 What is a variance in food service and when is it required?
ANS A variance is written permission from the regulatory authority to
use a non-standard food preparation method. Required for
activities like curing, smoking, sprouting seeds, or operating a
HACCP-based raw animal foods program.
Q23 What hand hygiene steps are required before handling food?
VERSION - TOP RATED (2026/2027)
Registered Environmental Health Specialist / Registered Sanitarian
2026 Trainee & Registered Level Exam Pack
Q1 What is the temperature danger zone for food?
ANS 40°F to 140°F (4°C to 60°C). Bacteria multiply rapidly within this
range and food should not remain in this zone for more than 2
hours (1 hour if ambient temp >90°F).
Q2 What is the minimum internal cooking temperature for
poultry?
ANS 165°F (74°C) for all poultry, including whole birds, ground poultry,
and stuffing.
Q3 Define HACCP and its purpose.
ANS Hazard Analysis and Critical Control Points (HACCP) is a
systematic preventive approach to food safety that identifies
physical, chemical, and biological hazards in production
processes. It is designed to prevent hazards rather than inspect
finished products.
Q4 What are the 7 HACCP principles?
ANS 1) Conduct hazard analysis, 2) Identify Critical Control Points
(CCPs), 3) Establish critical limits, 4) Establish monitoring
procedures, 5) Establish corrective actions, 6) Establish
, verification procedures, 7) Establish record-keeping and
documentation.
Q5 What is a Critical Control Point (CCP)?
ANS A step in the food production process where control can be
applied to prevent, eliminate, or reduce a food safety hazard to an
acceptable level.
Q6 What is the minimum cooking temperature for ground beef?
ANS 155°F (68°C) held for 15 seconds. This temperature destroys E.
coli O157:H7 and Salmonella.
Q7 What does 'FIFO' stand for in food storage?
ANS First In, First Out. This inventory management principle ensures
older stock is used before newer stock, reducing spoilage and
ensuring freshness.
Q8 What is the proper storage order from top to bottom in a
walk-in refrigerator?
ANS Top: Ready-to-eat foods. Below that: Seafood. Then: Whole cuts
of beef/pork. Then: Ground meats/fish. Bottom: Poultry (highest
cooking temp required).
Q9 What temperature must hot food be held at to prevent
bacterial growth?
ANS 140°F (60°C) or above. Hot holding equipment must maintain this
temperature throughout service.
Q10 What temperature must cold food be held at?
ANS 41°F (5°C) or below. This slows but does not eliminate bacterial
growth.
,Q11 What is the 2-hour/4-hour rule in food safety?
ANS Food in the danger zone 0–2 hours: can be used or refrigerated.
2–4 hours: must be used immediately. Over 4 hours: must be
discarded.
Q12 What are the Big 9 food allergens recognized by the FDA?
ANS Milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soybeans,
and sesame (added in 2023 under FASTER Act).
Q13 What is cross-contamination in food safety?
ANS The transfer of harmful microorganisms from one food, surface, or
person to another. This can be direct (raw meat touching ready-to-
eat food) or indirect (through shared equipment or hands).
Q14 What is the proper method for cooling cooked food?
ANS Cool from 135°F to 70°F within 2 hours, then from 70°F to 41°F
within an additional 4 hours (6 hours total). Methods: ice baths,
blast chillers, shallow pans.
Q15 What does pH measure and why is it important in food
safety?
ANS pH measures the acidity or alkalinity of food on a scale of 0–14.
Bacteria grow best between pH 4.6–7.5. Low pH (acid) inhibits
most pathogens; foods with pH below 4.6 are considered non-
PHF.
Q16 What is a Potentially Hazardous Food (PHF)?
ANS A food that supports bacterial growth: moist, protein-rich, and
neutral pH. Examples: meat, poultry, fish, dairy, cooked starchy
foods, cut melons, cooked legumes.
Q17 Define water activity (Aw) and its significance.
, ANS Aw is the measure of free water available for microbial growth (0–
1.0). Most bacteria require Aw ≥0.85. Foods with Aw <0.85 are
generally safe from bacterial spoilage.
Q18 What is Clostridium botulinum and how is it prevented?
ANS An anaerobic bacterium producing the most potent toxin known. It
thrives in low-acid, oxygen-free environments (canned goods).
Prevention: proper canning (pressure cooking), maintaining pH
<4.6, or Aw <0.93.
Q19 What are foodborne illness outbreak criteria?
ANS An outbreak is defined as two or more people experiencing similar
illness after eating the same food, confirmed by epidemiological
investigation. A single case of botulism or chemical poisoning may
also constitute an outbreak.
Q20 What is Norovirus and how is it transmitted?
ANS A highly contagious viral pathogen causing vomiting and diarrhea.
Transmitted via fecal-oral route, contaminated food/water, or
surfaces. One of the leading causes of foodborne illness in the
US.
Q21 What is the minimum cooking temperature for fish?
ANS 145°F (63°C) for 15 seconds. Parasitic destruction may require
specific time-temperature combinations or freezing protocols.
Q22 What is a variance in food service and when is it required?
ANS A variance is written permission from the regulatory authority to
use a non-standard food preparation method. Required for
activities like curing, smoking, sprouting seeds, or operating a
HACCP-based raw animal foods program.
Q23 What hand hygiene steps are required before handling food?
