Machines Exam Practice Questions And

FDNY G99 Use of Anhydrous Ammonia for Heat Treating (Dissociators) and Duplicating Machines Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary hazard associated with anhydrous ammonia in

heat treating operations?

• Corrosive fumes
• Flammability
• Toxicity
• Radioactivity

Rationale: Anhydrous ammonia is primarily a toxic chemical, capable

of causing severe respiratory and skin injuries upon exposure.

• What type of personal protective equipment (PPE) is required when

handling anhydrous ammonia?

• Standard gloves and apron 1 / 4

• Chemical-resistant gloves, goggles, and face shield
• Cotton lab coat
• No PPE is required

Rationale: Anhydrous ammonia can cause chemical burns and eye

injuries; chemical-resistant PPE is essential.

• What is the NFPA rating for anhydrous ammonia regarding health

hazard?

• 0
• 1
• 3
• 4

Rationale: Anhydrous ammonia is rated 3 for health hazards due to

its severe toxicity and potential to cause permanent injury.

• Which of the following is a correct method for detecting anhydrous

ammonia leaks?

• Use of water
• Ammonia detection monitors
• Smelling the air
• Using a flame test

Rationale: Detection monitors or sensors are safe and accurate;

smelling is unsafe due to toxicity.

• What is the first action to take in case of skin contact with anhydrous

ammonia? 2 / 4

• Apply ointment
• Cover with a dry cloth
• Flush immediately with copious amounts of water
• Seek medical attention after an hour

Rationale: Immediate flushing with water dilutes the chemical and

prevents further tissue damage.

• How should anhydrous ammonia cylinders be stored?
• Indoors near heat sources
• Upright, in a cool, well-ventilated area, away from incompatible

materials

• Lying on their side
• Buried underground

Rationale: Proper storage reduces risk of leaks, pressure buildup, and

accidental exposure.

• Which pressure condition is typical for anhydrous ammonia cylinders

at ambient temperature?

• 50 psi
• 100 psi
• 200-300 psi
• 500 psi

Rationale: Anhydrous ammonia is stored under pressure, usually

between 200-300 psi at room temperature. 3 / 4

• What is the primary chemical reaction hazard when anhydrous

ammonia contacts certain metals like copper or brass?

• Explosion
• Fire
• Corrosion and embrittlement
• No hazard

Rationale: Ammonia reacts with copper and its alloys, causing

corrosion and weakening the metal.

9. In a heat-treating dissociator, the ammonia is primarily used for:

• Cooling metals
• Nitriding to harden the metal surface
• Lubrication
• Cleaning

Rationale: Ammonia is used in nitriding processes to diffuse nitrogen

into metal surfaces, increasing hardness.

• Which of the following is an important ventilation requirement

in areas using anhydrous ammonia?

• Only natural ventilation
• Continuous mechanical ventilation with exhaust fans
• Occasional window opening
• Ventilation is optional

Rationale: Continuous mechanical ventilation prevents accumulation

of toxic ammonia vapors.

• / 4