According to the National Institute of Standards and Technology of the U.S

question 15

Multiple Choice

According to the National Institute of Standards and Technology of the U.S. Department of Commerce, a gas cylinder that is color-coded brown and green should contain which of the following?

• A) O₂-N₂ mixture
• B) O₂-CO₂ mixture
• C) CO₂
• D) O₂-He mixture

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Definitions:

Air-over-hydraulic Brakes

A braking system that uses air pressure to control the hydraulic fluid movement, thereby combining the advantages of both air and hydraulic braking systems.

Hydraulic Booster Assemblies

Components designed to enhance the efficiency of hydraulic systems by increasing the pressure or force applied within the system.

Quick Release Valves

Quick Release Valves are components in air braking systems that allow for rapid exhaust of air from the brake chambers, facilitating faster release of the brakes and reducing brake release time.

Combination Valve

Used in a hydraulic brake system, it contains the safety switch, metering, and proportioning valves in a single valve body and usually is located close to the master cylinder. Also may refer to other multiple function valves such as the service, emergency, relay valve (SERV) used on air brake systems.