Gases with a similar density to air, like carbon monoxide, should be detected within the “breathing zone,” which is typically between 4 to 6 feet (1.2 to 1.8 meters) from the floor—where most people breathe.
Heavier than air gases should typically be detected 6 in / 15 cm (sometimes 12 in / 30 cm) from the floor. Lighter than air gas sensors should typically be placed on or near the ceiling, and gases which have a density close to that of air should have sensors installed in the "breathing zone".
While leaking in their liquid forms, toxic compounds can flow downwards and spread into the lowest areas. The detectors should be installed at low levels (1 to 3 feet) above ground level.
The alarm must be located at least 3 feet, but not more than 10 feet from the appliance, measured horizontally. The gas alarm must be installed on either the ceiling, or a wall. Where installed on a wall, the alarm must be located not more than 12 inches from the ceiling.
Motion sensors usually work best when mounted between 6 and 8 feet off the floor. Ideal height is usually 7 feet. Although, different models might have different requirements — so check the manual of your specific sensor to know for sure.
The breathing zone refers to the area 4 - 6 ft / 1.2-1.8 m from the floor, where most human breathing takes place. This is a good default location for sensors, as many gases often disperse well in air. Sensors should be placed near the source of the gas if possible.
Refrigerant gases like hydrofluorocarbons (HFCs) are much heavier than air, so the refrigerant sensor should be mounted 4-6 inches (10-15 cm) off the floor. However, it is equally important if possible to place the sensor as close to the source of a potential leak, but not near a fan or other source of moving air.
Gas-detector sensitivity must be below the lowest PEL or TLV for health hazard gases and/or at or below 10–15% of the lower explosive limit (LEL) level for flammable gases.
We recommend the Kidde Nighthawk Carbon Monoxide and Explosive Gas Detector as the best overall gas leak detector. It detects a wide variety of explosive gases (including propane and natural gas), along with carbon monoxide, and it has two power sources for extra redundancy.
The International Association of Fire Chiefs recommends a carbon monoxide detector on every floor of your home, including the basement. A detector should be located within 10 feet of each bedroom door and there should be one near or over any attached garage. Each detector should be replaced every five to six years.
You can choose to not have the natural gas detector installed. However, the detector can provide valuable early warning of a gas leak emergency before it develops into a more serious situation, possibly involving a fire or an explosion. This could result in property damage, serious injuries, or death.
Combustible gas detection systems are typically arranged to signal an alarm at two different levels of gas concentration. The system could activate output alarm devices and also signal that a specific level of combustible gas exists. Two common alarm set points are 20% LEL and 40% LEL.
Natural gas is lighter than air, so it will rise and disperse if allowed to vent freely. Although rare, natural gas leaks can be dangerous and result in fire, explosions, injury or death. If you suspect a leak, call 1-800-ALLIANT (800-255-4268) immediately.
Piping installed outdoors shall be elevated not less than 31/2 inches (89 mm) above ground and where installed across roof surfaces, shall be elevated not less than 31/2 inches (89 mm) above the roof surface.
7. Readings must be above 19.5% O2 and below 23.5% O2, 10% LEL, 25 ppm CO, and 10 ppm H2S for legal entry into a space. EHS strongly recommends that individuals not enter atmospheres containing more than 21.5% oxygen, less than 20.5% oxygen, or more than 5% LEL, 10 ppm CO or 5 ppm H2S.
If you smell a sulfur or rotten-egg-like odor, you could have a gas leak. Natural gas is naturally colorless and odorless. We add an odorant called mercaptan to natural gas, which gives it a distinctive smell. In some cases, you can also identify natural gas by sight or sound.
Catalytic Bead gas detectors: Catalytic bead detectors detect combustible gases such as methane or propane. They rely on the combustion of gases on a heated wire to produce a signal. The lifespan of catalytic bead sensors can vary but generally falls within the range of around five years.
Does a Carbon Monoxide Detector Detect Natural Gas? To answer the question, "does a co detector detect natural gas," no, most carbon monoxide detectors will not detect natural gas, as they are different types of gas entirely. Also, most smoke detectors will detect carbon monoxide rather than natural gas.
National Fuel Gas Code
NFPA 54, ANSI Z223. 1 provides minimum safety requirements for the design and installation of fuel gas piping systems in homes and other buildings.
For example, a methane detector might have a calibration range of 0-100 ppm. The calibration gas would be somewhere in that range, say 50 ppm. The span gas might be 10,000 ppm methane. So, when you use it, you should get a reading near the upper limit of 100 ppm.
Gas detectors act as the first line of defence, rapidly alerting workers to immediate threats, while gas analysers offer deeper insights into the gas composition, both enabling informed decision-making and risk mitigation.
Sensors for heavier-than-air gases should generally be positioned 6 inches (15 cm) to 12 inches (30 cm) from the ground, as these gases tend to settle near the floor. For lighter-than-air gases, sensors are best placed near the ceiling or on high surfaces as these gases rise.
Place sensors in areas where air currents are likely to produce the highest gas concentration, including areas where gas buildup is likely, such as corners or stopping points of gas-releasing moving devices. Factor in the monitored gas's vapor density when compared to air.
Because carbon monoxide is slightly lighter than air and also because it may be found with warm, rising air, detectors should be placed on a wall about 5 feet above the floor. The detector may be placed on the ceiling. Do not place the detector right next to or over a fireplace or flame-producing appliance.