Devices Contractor Exam Questions

CA D28 Doors Gates & Activating Devices Contractor Exam Questions And Correct Answers (Verified Answers) Plus Rationale2026 Q&A| Instant Download Pdf

Which type of door is most suitable for high-traffic commercial entrances?

• Swing door
• Sliding door
• Revolving door
• Folding door
• Revolving door

Rationale: Revolving doors allow continuous entry and exit, reduce air

infiltration, and handle high traffic efficiently.

• What is the primary purpose of a door closer?
• To lock the door automatically
• To provide smooth and controlled door closure
• To prevent drafts
• To act as a fire barrier
• To provide smooth and controlled door closure

Rationale: Door closers regulate the speed and force of door closing,

enhancing safety and convenience.

• Which gate type is ideal for limited space and requires minimal swing

area?

• Sliding gate
• Swing gate
• Bi-folding gate 1 / 3

• Turnstile gate
• Sliding gate

Rationale: Sliding gates move horizontally along a track and require

less clearance than swing gates, making them suitable for tight spaces.

• In an automatic sliding door system, which component detects the

presence of a person?

• Motor
• Sensor
• Guide rail
• Track roller
• Sensor

Rationale: Sensors, such as motion or infrared sensors, detect

approaching people and trigger the door to open automatically.

• What is the recommended minimum width for a single wheelchair-

accessible door?

• 750 mm
• 800 mm
• 850 mm
• 900 mm
• 800 mm

Rationale: Accessibility standards require a minimum clear width of

800 mm for wheelchair users to pass comfortably.

• Which material is most commonly used for fire-rated doors?
• Solid timber
• Hollow steel
• Tempered glass
• Aluminium
• Hollow steel

Rationale: Hollow steel doors with appropriate cores provide fire

resistance while maintaining structural integrity.

• What type of lock provides the highest security for external doors?
• Mortise lock
• Rim lock
• Padlock
• Tubular lock
• Mortise lock 2 / 3

Rationale: Mortise locks are embedded within the door, offering

stronger resistance to tampering and forced entry.

• For a gate operated by a remote-controlled motor, what safety feature is

essential to prevent injury?

• Motion sensor
• Emergency stop button
• Magnetic lock
• Key override
• Motion sensor

Rationale: Motion sensors detect obstacles in the gate path and stop

or reverse operation, preventing accidents.

• Which type of door is most appropriate for a cleanroom environment?
• Swing door
• Sliding door
• Revolving door
• Bi-fold door
• Sliding door

Rationale: Sliding doors minimize air turbulence, reduce

contamination risk, and optimize space in controlled environments.

• What is the main advantage of hollow metal doors over solid wood

doors?

• Lighter weight and higher fire resistance
• Cheaper to install
• Easier to paint
• Better sound insulation
• Lighter weight and higher fire resistance

Rationale: Hollow metal doors provide strength, durability, and fire

resistance while being lighter than solid wood doors.

• Which standard should a contractor refer to when installing

automatic doors in public buildings?

A. ISO 9001

B. EN 16005

C. ASTM E84

D. BS 476

B. EN 16005

Rationale: EN 16005 sets safety and performance requirements for

powered pedestrian doors to ensure safe operation.

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