Yes, CCTV cameras can record sounds if they are equipped with built-in microphones or have an external microphone attached. However, recording audio may be subject to legal regulations and privacy concerns, so it's important to check local laws before enabling audio recording.

Hikvision CCTV Camera: DS-2CD2143G0-I: Known for its high resolution (4MP) and robust build, suitable for both indoor and outdoor use.
CP Plus CCTV Camera: CP-USC-TA24L2: Offers good video quality (2MP) and night vision, popular for home and small business security. Dahua CCTV Camera: DH-IPC-
HFW1220S: Provides excellent video quality (2MP), weather resistance, and infrared night vision.
Godrej CCTV Camera: SeeThru Pro: Known for its reliability, good resolution (2MP), and user-friendly app for remote monitoring.

The life expectancy of CCTV camera systems typically ranges from 5 to 10 years. This can vary based on factors such as the quality of the cameras and equipment, environmental conditions, maintenance practices, and technological advancements. Regular maintenance and updates can help extend the lifespan of a CCTV system.

Conventional fire alarm systems use multiple circuits (zones) and can only identify the zone of an alarm, making maintenance more challenging. They are less expensive and simpler to install.
Addressable fire alarm systems use a single loop with unique addresses for each device, allowing for precise detection of the exact device and location of an alarm. This makes maintenance easier but comes at a higher cost and installation complexity.

A fire alarm system detects signs of fire (smoke, heat, or flames) using sensors, which send signals to a control panel. The control panel then activates audible and visual alarms to alert occupants and may automatically notify emergency services. Occupants evacuate, and responders arrive to manage the situation. Manual call points allow people to trigger alarms manually.

An access control system regulates entry by requiring users to present credentials like keycards, PINs, or biometrics to a reader. The system verifies these credentials against a database, and if valid, unlocks the door or gate. Each access attempt is logged for monitoring and security purposes. This ensures that only authorized individuals can enter specific areas.

A video door phone is a security device that allows homeowners to see and communicate with visitors at their door before granting access. It typically includes an outdoor camera with a microphone and a doorbell, and an indoor monitor with a screen and speaker. When a visitor presses the doorbell, the indoor unit displays the video feed from the camera, enabling the homeowner to have a conversation and decide whether to unlock the door.