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We are well-versed in early warning systems including air sampling, linear heat, hazardous gas and optical flame detection. These are just some of the options we specialize in to protect your property.
Air Sampling Smoke Detection/High Sensitivity Smoke Detection
Air Sampling Smoke Detection (ASSD) is also known as High Sensitivity Smoke Detection (HSSD) or Very Early Warning Smoke Detection. This type of fire detection system works by actively drawing air through a piping or tubing system to a centrally located detection assembly. The principle of the detection unit is very similar to a traditional smoke detector, which uses a light source projected across a small box and measures how much of the known amount of light is scattered or not allowed to pass to the other side of the box. By utilizing higher end light sources, such as multi-spectrum lasers, and more sophisticated light measuring devices, these units go beyond seeing the smoke. They can also determine the smoke color and particle sizes, as well as discriminate between dust, dirt, and smoke. Using these high-tech components along with data modeling and learning components, these systems can be programmed to be up to 1000 times more sensitive than traditional smoke detectors. This allows for warning of a prefire condition, which gives personnel time to investigate or correct the situation before smoke, heat, and flame can damage the protected property.
Analog Intelligent Smoke Detection
Analog intelligent smoke detectors look like typical smoke detectors; however, they are designed to report their information to an addressable fire detection panel. Where a traditional spot type smoke detector can only interpret a preset volume of smoke exceeding a set point, an analog intelligent detector can send the panel data beyond ‘on’ or ‘off.’ The detector can also be given a unique identifier so the fire panel can interpret not only the condition and state of the detector, but also exactly which unit is reporting its information to the fire panel.
Hazardous Gas Detection/Combustible Gas Detection
Gas detection systems are electronic devices designed to detect various types of combustible or toxic vapors. Common uses are the detection of vapors from cleaning solvents; fuel and other hydrocarbons; ammonia; carbon monoxide; and other poisonous vapors.
Most units utilize an electronic element calibrated to change state as an amount of product vapor is introduced to the point at where the detection unit is placed. This detection element’s change of state is interpreted by a small controller that can then provide a digital readout, dry contacts, or 4-20 milliamp output for integration into process control or building automation systems. Today, the more high tech units measure changes in wavelength transmission of a beam of infrared light across a small detection chamber to determine an amount of vapor near the detection unit. This provides a more robust unit capable of being washed or flooded without causing permanent failure.
Linear Heat Detection
Basic linear heat detection is designed to detect a fire through heat buildup from a fire event. Most systems work on the principal of a pair of wire conductors separated by a membrane that will melt at a defined temperature. This allows the wires to come in contact with each other, which causes an alarm. This wire bundle is then wrapped in various types of outer jackets, depending on the environment the wire will be used in.
Although this system can be used in any application requiring heat detection, typical applications include interiors of electrical cabinets, tunnels, freezer and refrigerated warehouses, aircraft hangers, and many other large areas. Ease of installation makes this system ideal of large areas requiring cost effective fire detection.
Today, these systems simulate the twisted wires with fiber optic cable. By measuring the changes in the way light transmits through a fiber optic cable, an exact temperature at a precise point over the fiber optic cable can be interpreted into an alarm.
Optical Flame Detection
Optical flame detection utilizes electronic detection assemblies measuring a spectrum of light that can in turn be interpreted by on-board processors or controllers. By comparing the spectrum, intensity, and flicker or pulsing of the light, and processing it with a program of manufacturer algorithms, it can be compared to a known signature of a type of flame. The processor will then trigger an alarm or action. Many of the original flame detection technologies were prone to false alarms caused by other types of light that looked similar to the flame the unit was designed to see. The lack of intelligence or processor technology limited these original units. There is little comparison of today’s technology and those of years past.
Video Image Smoke/Flame Detection
Video Image Fire Detection is the newest technology to be added to the fire detection technology options list. At its simplest form, think of the way your eyes see flame or smoke. You see an image, which is interpreted by your brain based on past knowledge and learning from previous situations. From that data, you make a determination of what action to take. These systems analyze each pixel of a video camera’s digital image, and compare them to a base image using manufacturer algorithms to determine differences. Actions can be programmed to create warnings and alarms. Not to be confused with optical flame detectors or beam type smoke detectors, these units are truly utilizing the full visual image - not just electronically analyzing them for a spectrum of light specific to a flame. The advantage of these systems over other detection technology is the ability to have a recorded history of the video image. This video image can be marked, tagged, flagged, stored, archived, and played back. It can also be remotely viewed over the internet or sent to smart phones. The best units are approved by Factory Mutual; UL Listed, and meet all requirements of NFPA 72 for fire detection devices.