What is a quick opening device on a sprinkler system?
Quick Opening Devices (QOD) are predominately used in dry pipe sprinkler systems to speed the operation of the dry pipe valve (trip time), resulting in quicker water delivery time (trip time + transit time). There are two principal types of quick opening devices – accelerators and exhausters.
What are the three basic categories of preaction sprinkler systems?
There are three different types of preaction systems, a non-interlock system, a single interlock system, and a double interlock system.
What type of detectors most common are normally used to activate a preaction system?
Thermal detectors are the most frequently-used releasing devices in preaction and deluge systems.
What is the purpose of an accelerator on a dry sprinkler system?
The most common are accelerators, which quickly sense rapid air pressure drops and push pressurized air into the dry valve to upset its differential faster. Exhausters discharge large amounts of pressurized air directly into the atmosphere instead of waiting for it to escape through the sprinkler.
What is a bypass connection on a sprinkler system?
A bypass connection is a pipe connection between the suction and discharge side of a booster set in order to bypass water when the pumps are not in operation. The pipe diversion consists of a manifold, two isolating valves and a non-return valve.
What is deluge sprinkler system?
Deluge suppression systems are typically used in special hazard installations when water must be applied to an entire area for fire protection. These systems are considered a ‘dry fire protection system’ as the piping for the system is empty and at an atmospheric pressure with the sprinkler heads all open.
What is a Vesda system?
The VESDA system is a “very early warning aspirating smoke detection” and is designed to alarm you to the danger as soon as possible. The VESDA air sampling fire detection system detects invisible by-products of materials as they degrade during the precombustion stages of a developing fire.
Which type of alarm verification is commonly used with preaction systems?
Which type of alarm verification is commonly used with preaction systems? cross-zoning.
What is a backflow bypass?
A type-II bypass is used on a detector backflow assembly, which consists of a main valve, with 2 checks, and a bypass valve, with either 2 checks (standard type-I bypass) or 1 check (modern type-II bypass). The type-II bypass valve connects upstream and downstream of the main second check valve.
What is the difference between a dry system and a pre-action system?
Pre-Action Fire Sprinkler Systems: Like dry pipe systems, pre-action pipes do not hold water within the sprinkler piping and are instead filled with compressed air or nitrogen. Unlike a dry pipe system, the pre-action valve governs the flow of water.
What is the difference between single and double interlock preaction systems?
A single interlock system is activated only upon the event of detection device activation. Two separate events must happen; sprinkler activation and detection device activation, before water is admitted into a double interlock system.
Is VESDA a fire suppression system?
VESDA ® can also be used as a double knock system, which provides the most suitable fire detection model for any automatic fire suppression system!
What are the initiation devices?
Automatic Initiating devices
- Heat detectors.
- Smoke detectors.
- Duct detectors.
- Beam detectors.
- Tamper switches.
- Fire sprinkler water flow switches.