Fire Alarm Systems Are Well-defined

B –NFPA 72, 2016, A.29.5.1

The use of 30 ft./min flow velocity in the UL 268 and 217 smoke detector sensitivity tests for spot-type smoke detectors has led to the evolution of spot-type smoke detectors that are optimized for that flow velocity. This means that these detectors have been designed and calibrated to perform at their best when subjected to a flow velocity of 30 ft./min. This flow velocity is considered to be the most effective for detecting smoke particles and ensuring accurate and reliable detection.

The phrase "notified in writing" in section 26.2.6.1 does not include email communications. Although correspondence that can be verified upon request is included, email communications are still not permitted.

B – NFPA 72, 2016, A.29.8.3

A – B4.10

Ultraviolet wavelengths are detected by radiant energy-sensing detectors in the range of 0.1 to 0.35 microns.

According to section 26.2.2.1, if an alarm signal cannot be reliably confirmed as a nuisance alarm, then it should be immediately retransmitted unless such determination can be made.

Working smoke alarms cut the risk of dying in a reported home structure by 50 percent. This means that having functioning smoke alarms in a home can significantly decrease the chances of fatalities in the event of a fire. Smoke alarms are designed to detect smoke and alert occupants, giving them valuable time to escape and seek safety. By providing an early warning, smoke alarms can greatly increase the likelihood of survival during a fire emergency.

A Class A system is one that utilizes a certain wiring scheme that is outlined in the Code. This means that the system is installed in a way that allows for redundancy and ensures that all devices will continue to operate even if there is a break or fault in the wiring. This wiring scheme is outlined in the Code to ensure the reliability and effectiveness of the system in the event of a fire or emergency.

Planckian emissions refer to the radiation emitted by a black body at a specific temperature. This type of emission is a result of the thermal energy present in the fuel mass. It is not specific to any particular type of fire or fuel source, such as gasoline fires or Class E fires. Additionally, Planckian emissions are not solely produced by combustible solids, as they can also be generated by liquids and gases.

The statement is false because the term "dwelling unit" is defined and applies to both one- and two-family dwellings as well as other occupancies. The question implies that the term only applies to occupancies other than one- and two-family dwellings, which is incorrect.

NRTLs rate flame detector sensitivity by using a fire of 1.0 square foot size using regular grade, unleaded gasoline. This means that the flame detector is tested and evaluated based on its ability to detect and respond to a fire of this specific size and fuel type. The use of a standardized fire size and fuel type allows for consistent and reliable testing of flame detector sensitivity across different models and manufacturers.

The term "immediately" used within the context of the Code is intended to mean without unreasonable delay. This means that action should be taken promptly and efficiently, but it does not necessarily require instantaneous action. The Code does not provide an exact timeframe for what constitutes "immediately", but it implies that there should not be any unnecessary or unreasonable delays in taking action. The determination of what is considered a reasonable delay may vary depending on the specific circumstances and the judgment of the Authority Having Jurisdiction (AHJ).

The correct answer is a. a maximum of four minutes. This means that the central station should not take more than four minutes to handle a supervisory signal before initiating communication with the designated person. This ensures that any issues or emergencies are addressed in a timely manner and reduces the risk of delays in communication.

B – B.4.9.1