NEHA Registered Environmental Health Specialist/Registered Sanitarian (REHS/RS) — Questions and Answers

Question 1: What is 'abatement' as used in environmental health enforcement?

The sampling of environmental media for contamination
The process of obtaining a permit for a regulated activity
The process of issuing a fine for a violation
The correction, elimination, or control of a nuisance, hazard, or violation to acceptable levels (Correct answer)

Correct answer: The correction, elimination, or control of a nuisance, hazard, or violation to acceptable levels

Abatement refers to the correction, elimination, or reduction of an environmental health hazard, nuisance, or regulatory violation to bring a condition into compliance or remove the threat.

Question 2: What is composting as a solid waste management strategy?

Burial of organic waste in sealed containers
Biological decomposition of organic materials into a stable humus-like product (Correct answer)
Chemical treatment of waste with solvents
Incineration at low temperatures

Correct answer: Biological decomposition of organic materials into a stable humus-like product

Composting is a controlled biological process that decomposes organic materials such as food scraps and yard waste into a stable, nutrient-rich product that can be used as a soil amendment.

Question 3: What is a 'Phase II Environmental Site Assessment' and when is it conducted?

A subsurface investigation involving soil and groundwater sampling to confirm or characterize contamination identified in a Phase I assessment (Correct answer)
An annual compliance monitoring report for a permitted facility
A remediation action plan for a contaminated site
A review of property records and databases before property purchase

Correct answer: A subsurface investigation involving soil and groundwater sampling to confirm or characterize contamination identified in a Phase I assessment

A Phase II ESA is conducted when a Phase I identifies recognized environmental conditions; it involves physical investigation including soil borings, groundwater monitoring wells, and laboratory analysis to determine whether contamination is present and its extent.

Question 4: The EPA recommends mitigation when indoor radon levels reach or exceed which concentration?

10 pCi/L
4 pCi/L (Correct answer)
20 pCi/L
2 pCi/L

Correct answer: 4 pCi/L

The EPA recommends taking action to reduce radon when levels reach 4 picocuries per liter (pCi/L) or higher in a home.

Question 5: Which tick species is the primary vector of Rocky Mountain spotted fever in the eastern United States?

Amblyomma americanum (lone star tick)
Ixodes scapularis
Rhipicephalus sanguineus (brown dog tick)
Dermacentor variabilis (American dog tick) (Correct answer)

Correct answer: Dermacentor variabilis (American dog tick)

Dermacentor variabilis, the American dog tick, is the primary vector of Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, in the eastern and central United States.

Question 6: Which mold genus is most commonly associated with water-damaged buildings and classified as a 'black mold' of public health concern?

Aspergillus niger
Penicillium notatum
Cladosporium herbarum
Stachybotrys chartarum (Correct answer)

Correct answer: Stachybotrys chartarum

Stachybotrys chartarum is the mold commonly called 'black mold' and is associated with chronic water damage; it produces trichothecene mycotoxins of public health concern.

Question 7: Which federal program requires landlords and sellers to disclose known lead-based paint hazards in pre-1978 housing before sale or lease?

Resource Conservation and Recovery Act
Clean Air Act Section 112
Residential Lead-Based Paint Hazard Reduction Act (Title X) (Correct answer)
National Environmental Policy Act

Correct answer: Residential Lead-Based Paint Hazard Reduction Act (Title X)

Title X of the Residential Lead-Based Paint Hazard Reduction Act mandates disclosure of known lead-based paint and hazards in pre-1978 housing transactions.

Question 8: Formaldehyde off-gassing in homes is most commonly associated with which building materials?

Pressed wood products (particleboard, MDF, plywood) (Correct answer)
Glass and ceramic tile
Concrete and masonry blocks
Fired clay bricks

Correct answer: Pressed wood products (particleboard, MDF, plywood)

Pressed wood products manufactured with urea-formaldehyde resins, including particleboard, MDF, and plywood, are the primary indoor sources of formaldehyde off-gassing in homes.

Question 9: What is the primary health concern from exposure to asbestos?

Mesothelioma, lung cancer, and asbestosis from inhalation of fibers (Correct answer)
Acute skin irritation and burns
Reproductive disorders from dermal contact
Liver toxicity and jaundice

Correct answer: Mesothelioma, lung cancer, and asbestosis from inhalation of fibers

Inhalation of asbestos fibers causes mesothelioma (cancer of the pleural lining), lung cancer, and asbestosis (progressive lung scarring), often with a latency period of decades between exposure and disease.

Question 10: Which of the following is a common indoor air pollutant that can cause respiratory issues?

Carbon monoxide (Correct answer)
Nitrogen dioxide
Sulfur dioxide
Ozone

Correct answer: Carbon monoxide

Carbon monoxide is a colorless, odorless gas that can accumulate indoors from faulty heating systems or combustion appliances, causing respiratory problems and other health issues.

Question 11: In hazardous materials response, what does the NFPA 704 diamond (fire diamond) communicate?

The price and availability of a chemical
The legal classification of the material under RCRA
The specific emergency response procedures required
Health hazard, flammability, reactivity, and special hazard information for emergency responders using a 0–4 rating scale (Correct answer)

Correct answer: Health hazard, flammability, reactivity, and special hazard information for emergency responders using a 0–4 rating scale

The NFPA 704 hazard identification system uses a diamond-shaped sign with four color-coded quadrants rating health (blue), flammability (red), instability/reactivity (yellow), and special hazards (white) on a 0–4 scale.

Question 12: Which of the following is the most common method used to disinfect drinking water?

Boiling
Fluoridation
Filtration
Chlorination (Correct answer)

Correct answer: Chlorination

Chlorination is the most widely used method to disinfect drinking water, killing bacteria, viruses, and other pathogens.

Question 13: What is 'biological control' in vector management, and provide a primary example used against mosquitoes?

Draining all wetlands to eliminate breeding sites
Using living organisms such as Bacillus thuringiensis israelensis (Bti) or Gambusia fish to kill or reduce mosquito populations (Correct answer)
Using electronic devices to repel mosquitoes
Applying synthetic pyrethroids to breeding areas

Correct answer: Using living organisms such as Bacillus thuringiensis israelensis (Bti) or Gambusia fish to kill or reduce mosquito populations

Biological control uses living organisms; Bti is a naturally occurring soil bacterium whose toxins kill mosquito larvae, and Gambusia (mosquitofish) consume mosquito larvae in permanent water bodies.

Question 14: What is the 'right-to-know' concept embodied in EPCRA (Emergency Planning and Community Right-to-Know Act)?

The right of communities to obtain information about hazardous chemicals stored or released by nearby facilities (Correct answer)
The right of employees to know pesticide ingredients
The right of regulators to know about planned facility expansions
The right of inspectors to access all facility records

Correct answer: The right of communities to obtain information about hazardous chemicals stored or released by nearby facilities

EPCRA gives communities the right to obtain information about hazardous chemicals present at nearby facilities and to be informed of toxic chemical releases through the Toxics Release Inventory (TRI) program.

Question 15: What is a 'complaint investigation' in environmental health practice, and what triggers one?

A federally mandated annual review of permitted facilities
An investigation initiated only when violations are discovered during routine inspections
A self-initiated routine inspection scheduled by department policy
An investigation initiated in response to a citizen, tenant, or employee report of a potential environmental health hazard or regulatory violation (Correct answer)

Correct answer: An investigation initiated in response to a citizen, tenant, or employee report of a potential environmental health hazard or regulatory violation

A complaint investigation is initiated when a member of the public, worker, or other party reports a suspected environmental health hazard or violation; the complaint provides the trigger and direction for the investigative response.

Question 16: What is the health significance of polycyclic aromatic hydrocarbons (PAHs) in environmental health?

They are synthetic flavoring agents in processed food
They are useful disinfectants in water treatment
They are persistent organic pollutants formed during incomplete combustion that are carcinogenic and mutagenic (Correct answer)
They are beneficial nutrients found in whole grains

Correct answer: They are persistent organic pollutants formed during incomplete combustion that are carcinogenic and mutagenic

PAHs are a group of persistent organic pollutants formed during incomplete combustion of organic materials that are classified as probable or possible carcinogens and can cause mutagenic and genotoxic effects.

Question 17: Which particulate matter (PM) size is most harmful to human health because it can penetrate deep into the lungs?

PM2.5 (Correct answer)
PM50
PM10
PM1

Correct answer: PM2.5

PM2.5 consists of fine particles with a diameter of 2.5 micrometers or less, which can penetrate deep into the lungs and even enter the bloodstream, causing serious health issues.

Question 18: What is 'resistance management' in the context of pesticide use for vector control?

Increasing pesticide doses to overcome resistance
Using only organochlorine pesticides
Banning all pesticide use
Rotating pesticide classes and using non-chemical methods to prevent development of pesticide-resistant pest populations (Correct answer)

Correct answer: Rotating pesticide classes and using non-chemical methods to prevent development of pesticide-resistant pest populations

Resistance management involves rotating pesticide classes with different modes of action and integrating non-chemical control methods to slow the development of genetically resistant pest populations.

Question 19: What is the purpose of a 'Preliminary Site Investigation' (PSI) at a potentially contaminated property?

To obtain a building permit for site development
To conduct laboratory analysis of soil and groundwater samples
To gather existing information and conduct site reconnaissance to determine whether a recognized environmental condition exists before committing to detailed investigation (Correct answer)
To conduct full remediation of identified contamination

Correct answer: To gather existing information and conduct site reconnaissance to determine whether a recognized environmental condition exists before committing to detailed investigation

A PSI (also called Phase I ESA) reviews historical records, databases, and site conditions to identify recognized environmental conditions that may indicate contamination, guiding decisions about whether further investigation is needed.

Question 20: Which federal law is the primary statute governing solid waste disposal in the United States?

Clean Air Act
Comprehensive Environmental Response Act
Safe Drinking Water Act
Resource Conservation and Recovery Act (RCRA) (Correct answer)

Correct answer: Resource Conservation and Recovery Act (RCRA)

RCRA, enacted in 1976, is the principal federal law governing the disposal of solid and hazardous waste in the US.

Question 21: What is the primary health concern associated with cockroach infestations in residential housing, beyond direct disease transmission?

Carbon monoxide poisoning
Radon gas accumulation
Lead contamination of food
Allergen production triggering asthma (Correct answer)

Correct answer: Allergen production triggering asthma

Cockroach frass (feces), cast skins, and saliva contain potent allergens that are a leading trigger of asthma attacks, particularly in children living in infested urban housing.

Question 22: What is 'ultra-low volume (ULV)' spraying used for in adult mosquito control programs?

Treating standing water with larvicides
Dispersing very small droplets of pesticide at low application rates to contact flying adult mosquitoes (Correct answer)
Applying large volumes of diluted pesticide to vegetation
Applying rodenticides in bait stations

Correct answer: Dispersing very small droplets of pesticide at low application rates to contact flying adult mosquitoes

ULV spraying disperses extremely fine pesticide droplets (typically 1–50 microns) at very low volume rates so they remain airborne long enough to contact and kill flying adult mosquitoes.

Question 23: What is the minimum daily cover requirement for active sanitary landfill working faces under federal criteria?

12 inches of soil or approved alternative
3 inches of soil or approved alternative
18 inches of soil or approved alternative
6 inches of soil or approved alternative (Correct answer)

Correct answer: 6 inches of soil or approved alternative

Federal criteria under 40 CFR Part 258 require a minimum of 6 inches of earthen material or approved alternative as daily cover to control vectors, fires, odors, and litter.

Question 24: What is sludge in the context of wastewater management?

The gas produced during treatment
The chemical used in disinfection
The solid waste produced from wastewater treatment (Correct answer)
The clean water after treatment

Correct answer: The solid waste produced from wastewater treatment

Sludge is the thick, semi-solid byproduct of wastewater treatment, consisting of organic matter, microorganisms, and other solids removed during the treatment process.

Question 25: How long can perishable food be safely left out at room temperature?

2 hours (Correct answer)
1 hour
4 hours
3 hours

Correct answer: 2 hours

Perishable foods should not be left out at room temperature for more than 2 hours to reduce the risk of bacterial growth.

Question 26: Which solid waste management strategy is ranked highest in the EPA's solid waste management hierarchy?

Composting
Energy recovery
Source reduction and reuse (Correct answer)
Recycling

Correct answer: Source reduction and reuse

Source reduction and reuse are ranked highest in the EPA hierarchy because preventing waste generation is more effective than managing waste after it is created.

Question 27: Which solid waste material poses a risk of puncture injury and is classified as a special waste requiring specific management?

Aluminum cans
Glass containers
Medical sharps (needles, lancets) (Correct answer)
Cardboard packaging

Correct answer: Medical sharps (needles, lancets)

Medical sharps such as needles and lancets are classified as special wastes due to their risk of puncture injury and potential for disease transmission.

Question 28: Overcrowding in housing is most commonly defined by environmental health standards as more than how many persons per room?

2 persons per room
1 person per room (Correct answer)
1.5 persons per room
0.5 persons per room

Correct answer: 1 person per room

HUD and the Census Bureau define overcrowding as more than 1 person per room (excluding bathrooms), and severe overcrowding as more than 1.5 persons per room.

Question 29: What is the purpose of the National Pollutant Discharge Elimination System (NPDES) permit program?

To set drinking water quality standards
To regulate discharges of pollutants from point sources into waters of the United States (Correct answer)
To regulate air emissions from industrial facilities
To manage solid waste disposal at landfills

Correct answer: To regulate discharges of pollutants from point sources into waters of the United States

The NPDES permit program, established under the Clean Water Act, regulates the discharge of pollutants from point sources into surface waters, requiring permits that specify effluent limits.

NEHA Registered Environmental Health Specialist/Registered Sanitarian (REHS/RS)

The REHS/RS credential exam tests environmental health specialists on surveillance, inspections, investigations, compliance review, and public communication across food safety, water, waste, and hazardous materials domains.

Questions

30 min

Time Limit

68%

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