Fire sprinklers are designed to be activated automatically in response to specific environmental conditions, primarily heat. Here's how fire sprinklers are activated:
1. Heat Detection: Fire sprinklers are equipped with heat-sensitive components, such as a fusible link or a heat-sensitive glass bulb, located within the sprinkler head. These components are designed to respond to a particular temperature threshold.
2. Temperature Increase: In the event of a fire, the heat generated by the flames causes the surrounding air temperature to rise. When the air temperature at the sprinkler head reaches the specified activation temperature, the heat-sensitive component reacts.
3. Activation Mechanism: There are two common types of activation mechanisms for fire sprinklers:
a. Fusible Link: In a fusible link system, a small metal link or plate inside the sprinkler head is designed to melt at the predetermined temperature. When the link melts due to the heat, it releases a seal or stopper that holds back water in the sprinkler system.
b. Heat-Sensitive Glass Bulb: Some sprinklers use a heat-sensitive glass bulb filled with a heat-sensitive liquid. As the temperature increases, the liquid inside the bulb expands, causing the glass to break. This rupture allows water to flow through the sprinkler head.
4. Water Release: Once the activation mechanism is triggered, it opens a pathway for pressurized water in the sprinkler system to flow through the sprinkler head. The water is discharged in a spray or spray pattern designed to suppress the fire and cool the surrounding area.
5. Localized Fire Suppression: Fire sprinklers are typically activated individually or in small groups, responding only to the immediate area where the temperature threshold has been reached. This localized activation minimizes water usage while effectively controlling or extinguishing the fire in the vicinity.
6. Building-Wide Alarm: In many cases, the activation of a fire sprinkler also triggers the building's fire alarm system, alerting occupants and notifying emergency services. The fire alarm system may activate audible and visual alarms and alert local authorities.
Fire sprinklers are highly effective in controlling fires because they respond automatically to heat conditions, even when occupants are not present or conscious of the fire. This automatic response helps prevent the spread of the fire, reduce property damage, and protect lives by controlling the fire until firefighters arrive. Fire sprinklers are a critical component of fire protection systems and play a vital role in fire safety.