Toxic and Combustible Gasses – Safety is Paramount

 

On January 31, 2022, a fire at a North Carolina fertilizer manufacturing facility caused officials to urge residents living nearby to stay away from their homes due to an increased risk of a possible explosion at the facility. People with respiratory issues were likewise advised to take precautions to minimize their potential exposure to toxic gasses.

According to Winston-Salem fire chief William Mayo, there were nearly 600 tons of ammonium nitrate and 5,000 tons of finished fertilizer at the site, enough to cause one of the worst explosions in U.S. history.

Ammonium nitrate is widely used to manufacture fertilizers for commercial and residential use. However, when exposed to extreme heat, ammonium nitrate may produce nitric oxide and ammonia (NH₃), which can create not only a toxic environmental situation but also a catastrophic explosion.

What is Nitric Oxide?

Nitric oxide (NO) is a poisonous and highly reactive gas that is colorless at room temperature, with a strong, sweet odor; it can be toxic when inhaled. Although NO is non-flammable, it will react to combustible materials and may increase the risk of fire and explosions if it is exposed to chlorinated hydrocarbons, carbon disulfide, fluorine, alcohol, petroleum, toluene, or ammonia. Nitric oxide can quickly oxidize to form nitrogen dioxide (NO₂).

What is Nitrogen Dioxide?

Nitrogen dioxide is a red-brown gas with an irritating, sharp odor. Like nitric oxide, NO₂ is non-flammable but can accelerate the burning of combustible materials.

What is Ammonia?

Ammonia (NH3) is a colorless gas with a pungent odor. Ammonia is not highly flammable, but it may react violently when exposed to fluorine, chlorine, nitrogen dioxide, or hydrogen bromide, among other gasses. Ammonia can produce poisonous gas during a fire.

Health Hazards

Exposure to nitric oxide, nitrogen dioxide, and ammonia can irritate the eyes, nose, and throat. At higher concentrations, NO, NO₂, and NH₃ can cause pulmonary edema (a build-up of fluid in the lungs). Prolonged exposure to nitric oxide and/or nitrogen dioxide may reduce the blood’s ability to transport oxygen, causing headaches, fatigue, dizziness, nausea, vomiting, unconsciousness, and even death.

Continued exposure to ammonia may cause asthma-like allergy symptoms and, possibly, permanent lung damage.

Workplace Exposure Limits

According to the Occupational Safety and Health Administration (OSHA), the permissible exposure limits (PELs) for nitric oxide, nitrogen dioxide, and ammonia are set forth below:

• Nitric Oxide: 25 parts-per-million (ppm) over an 8-hour work shift; it is immediately dangerous to health at 100 ppm
• Nitrogen Dioxide: 5 ppm, not to be exceeded at any time
• Ammonia: 50 ppm over an 8-hour shift.

Monitoring Hazardous Gasses

Nitric oxide, nitrogen dioxide, and ammonia can all react explosively if they mix with incompatible compounds. Further, exposure to fire may produce additional toxic and corrosive gasses. To help prevent an accidental leak and risk of explosion, gas cylinders should be stored in cool, well-ventilated areas, away from moisture and direct sunlight.

While nitric oxide, nitrogen dioxide, and ammonia all have strong odors, that is not necessarily an adequate warning of their presence, since prolonged exposure to NO₂, NO, and NH₃ can desensitize one’s sense of smell, thereby reducing awareness of the exposure.

To detect, and protect against, risks emanating from excessive concentrations of nitric oxide, nitrogen dioxide, or ammonia, best practices include placing gas detection monitors (containing visual and audible alarms) in locations where NO, NO₂, and NH₃ may accumulate. The gas detection system should continuously monitor the area and, if gas concentrations exceed the permissible exposure limit, activate an alarm, turn off the gas at the source, and turn on the ventilation system.

PureAire Monitors

PureAire Monitoring System's ST-48 Gas Detector is perfect for tracking levels of toxic and/or combustible gasses including, but not limited to, nitric oxide, nitrogen dioxide, and ammonia.

The ST-48 is housed in a NEMA 7 explosion-proof enclosure suitable for Class 1, Division 1 and 2, Groups A, B, C, and D, making it ideal for locations where toxic and/or combustible gasses are present or may accumulate.

PureAire’s ST-48 offers continuous readings of toxic and/or combustible gasses and features an easy-to-read screen, which displays current gas levels, in either ppm or lower explosive limit (LEL),  for at-a-glance observation. In the event of an accumulation of gasses to an unsafe level, the Detector will set off an alarm, complete with horns and flashing lights, alerting personnel to evacuate the area. The PureAire Gas Detector can likewise be programmed to tie into automatic shut-off valves, and ventilation systems when gas levels reach a user-selectable ppm or LEL.

The ST-48 Gas Detector can connect to multi-channel controllers, a remote display, or into building systems themselves.

Coming Clean on Chlorine Safety

 

What is chlorine?

Chlorine gas (CL₂) is a dense, yellow-green gas that has a distinctive, irritating odor that is similar to bleach and is almost instantly noticeable even at very low concentrations. While CL₂ is not flammable, it may react explosively when exposed to other gases, including acetylene, ether, ammonia, natural gas, and hydrogen, among others. Due to its reactivity, chlorine is rarely used in its pure form but instead is typically combined with other elements.

If you have ever taken a dip in a swimming pool, you are more than likely familiar with chlorine and its distinctive odor, as well as the burning sensation that sometimes affects the eyes. Chlorine is widely used as a disinfectant in swimming pools and in a variety of residential and industrial cleaning solutions, as well as in many everyday products.

Applications and Benefits of Chlorine Use

Chlorine gas is commonly used in water and wastewater treatment facilities to disinfect water and kill contaminants, thereby helping to prevent water-borne diseases such as cholera, typhoid fever, dysentery, and hepatitis A. In the same way, many people use chlorine bleach to disinfect and whiten laundry, as well as on household surfaces to kill germs such as norovirus, E.coli, salmonella, and other pathogens.

In addition to its disinfectant properties, CL₂ is used in a variety of applications by a large number of industries. For instance:

• The automobile industry utilizes chlorine in the manufacture of seat cushions and covers, headlamp lenses, tire cord, bumpers, sealants, paint, fan belts, airbags, brake fluids, and navigation systems.
• Pharmaceutical manufacturers utilize chlorine in the production of medicines such as pain relievers, allergy medications, and drugs to help lower cholesterol.
• Many industrial solvents, dyes, plastics, epoxy resins, and synthetic rubbers (such as neoprene), use chlorine in their manufacturing processes.
• The paper and textile industries use chlorine to bleach paper and textiles.
• Technology firms use chlorine in the production of a diverse array of goods, including microprocessors for smart phones and computers, pc boards, lasers, fiber optic cables, hybrid car batteries, satellite guidance systems, etc.

Chlorine Safety

Well-known to be potentially hazardous to health, chlorine was one of the first poison gases used as a weapon during World War I.

Contact with chlorine can severely irritate and burn the eyes and skin. Exposure can also cause headaches, dizziness, nausea, and vomiting.

At high concentrations, and with prolonged exposure, inhalation of chlorine can cause sore throat, wheezing, coughing, chest tightness, pulmonary edema, permanent lung damage, and even death. While chlorine’s strong odor can provide some warning of its presence, prolonged exposure to chlorine can desensitize one’s sense of smell, thereby reducing awareness of the exposure.

Monitoring Chlorine

According to The Occupational Safety and Health Administration, the permissible exposure level for chlorine is 1 part-per-million (ppm), which should not be exceeded at any time.  Chlorine is considered to be immediately dangerous to life and health when exposure levels reach 10 ppm.

To detect, and protect against, risks emanating from excessive concentrations of chlorine, best practices include placing gas detection monitors (containing visual and audible alarms) in locations where CL₂ may accumulate. The gas detection system should continuously monitor the area and, if chlorine concentrations exceed the permissible exposure limit of 1.0 ppm, activate an alarm, turn off the chlorine at the source, and turn on the ventilation system.

PureAire's Universal Gas Detector

PureAire Monitoring Systems’ Universal Gas Detectors use “smart” sensor cell technology to continuously track levels of chlorine. The sensor cell is programmed to monitor for a specific gas (in this case, chlorine) and measurement range, as required by the user.

PureAire's Universal Gas Detectors allow manufacturers to monitor chlorine levels before employee health is put at risk. In the event that CL₂ is elevated to an unsafe level, the Universal Gas Detector will set off an alarm that includes horns and flashing lights, alerting staff to vacate the affected area. At the same time, the monitor can be programmed to turn on the ventilation system.

The Universal Gas Detector's easy to read screen makes it simple for employees to monitor chlorine gas levels at a glance, giving them peace of mind as they work with this useful but hazardous gas.

From Farm to Market: Fruit Ripening

Fruit has a brief window where it is perfectly ripe. If farmers waited until every piece of fruit was ripe before harvesting, farming would be more labor-intensive as farmers rushed to pick ripe fruits. Prices might crash due to a short-term glut of fruit on the market. To ensure a steady supply and demand, keep prices competitive, and reduce food waste, farmers use artificial ripening procedures. One method for ripening fruit after harvest involves ripening chambers. Ripening chambers using ethylene, a natural plant hormone, enable the fruit to be harvested, stored, and transported to where it will be marketed and consumed. While ethylene ripening chambers are beneficial, they are not without risks.

How Ethylene Ripening Chambers Work

While there are other ways to artificially ripen fruit in ripening chambers, ethylene has become a favorite, since it occurs naturally in fruit.
Ethylene is a natural hormone found in plants. Fruits begin to ripen when exposed to ethylene, whether the exposure occurs naturally or artificially. In ethylene ripening chambers, unripe fruits are laid out, and the chamber is sealed.Ethylene gas is then piped into the sealed chamber. As the fruit is exposed to ethylene, the fruit
“respires”,which involves intake of oxygen andemission of carbon dioxide. For the ripened fruit to have the right color and flavor, the ripening should occur in a controlled atmosphere in which the temperature, humidity, ethylene, oxygen, and CO2 concentrationaremaintained at optimum levels.
However, there is a risk of combustion from the ethylene gas, as well as decreased levels of oxygen and increased levels of carbon dioxide inside the chamber.

How Oxygen/Carbon Dioxide and LEL Combustible Monitors Protect Employees

Low oxygen levels cause respiratory distress. If oxygen levels drop below the safe threshold for breathing, which could happen in the event of an ethylene gas leak, employees could suffocate. Suffocation is also a danger when there is too much carbon dioxide in the air. Ethylene gas used in ripening chambers would be hazardous if an employee were to enter the chamber before determining that oxygen and carbon dioxide were at safe levels.

A dual oxygen/carbon dioxide (O2/CO2) monitor detects the levels of oxygen and carbon dioxide within the chamber and sounds an alarm should the oxygen level falls to an OSHA action levelor if the carbon dioxide rises to an unsafe level.  By checking the monitor’s display, an employee will know when it is safe to enter the chamber.

PureAire Monitoring Systems has developed its dual O2/CO2 monitor with zirconium oxide and non-dispersive infrared sensor (“NDIR”) cells. The cells are unaffected by changing barometric pressure, storms, temperatures, and humidity, ensuring reliable performance.  Once installed, the dual O2/CO2 monitor needs no maintenance or calibration.

Ethylene is a highly flammable and combustible gas. If the gas lines used to pipe ethylene into the ripening chambers were to develop a leak, the chamber could fill with ethylene and reach combustible levels. A combustible gas monitor, which takes continuous readings of combustible gases, would warn employees of an ethylene leak within the chamber.

PureAire Monitoring System's Air Check LEL combustible gas monitor continuously monitors for failed sensor cell and communication line breaks. The Air Check LEL gas monitor is housed in an explosion-proof enclosure. If a leak or system error should occur, an alarm will immediately alert employees.

To learn about PureAire Monitoring Systems’ dual O2/CO2 monitors or the Air Check LEL Combustible monitor, please visit www.pureairemonitoring.com.

Why Gas Distributors Play a Crucial Role in Most Everyday Businesses?

Inert gases power a wide range of industries, including pharmaceutical, automotive, manufacturing, and semiconductor. While argon, helium, nitrogen, and cryogenic gases have benefits and uses, there are also risks with other gases such as halogens, refrigerants, combustibles, or etching gases. Gas detectors can monitor storage areas and facilities where these gases are used to guard against gas leaks onsite. Learn why it's critical to use one of these monitors in combustible gases distribution facilities.

The Role of Gas Distributors

Unless companies are manufacturing their own gases onsite through, for instance, a nitrogen generator, they rely on prompt delivery of gases they need for operation.

Gas distributors store a range of inert gases for use by manufacturers. Industry regulations mandate that gas distributors follow certain guidelines for the storage and disposal of these substances to reduce the risk of fires, explosion, gas leaks, and other incidents.

When everything is working correctly, gas flows as its needed from the supply tank to, for instance, storage dewars which are then readied for delivery. If a supply line develops a leak or a storage tank is not properly sealed, gas will leak into the air.

Many of these gases have no smell, color, or odor. This means that even if a facility is following all regulations regarding gas storage, there is no way that an employee could detect a gas leak in the moment when something goes wrong.

If storage dewars are compromised, gas will leak in the storage truck and at the delivery site, spreading the risk to third parties.

When one of these toxic gases leaks into the air, the consequences are dangerous. Hydrofluoric acid, a highly corrosive substance, is harmful to the health when it's inhaled or in direct contact with skin. Ammonia, which is commonly used as a refrigerant and in paper making, irritates the skin, lungs, and eyes.

Some gases are flammable when in contact with oxygen, which elevates the risk of fire. Others, like nitrogen, deplete oxygen from the environment. When oxygen drops below a critical threshold, workers can experience respiratory distress, cognitive distress, and ultimately death via asphyxiation.

To provide fast notification and decrease the risk of health hazards, it is recommended to install a universal gas detector wherever toxic gases are used or stored. To further guard against leaks, gas distributors can invest in durable equipment and train staff on proper handling of substances and appropriate emergency responses.

How a Universal Gas Monitor Can Protect Your Staff

A universal gas monitor can detect levels of gases even when the eye and nose cannot.

OSHA, the Occupational Safety & Health Administration, oversees worker safety in all environments, including gas distribution plants. OSHA requirements to prevent workers from being harmed at work include the use of a gas monitor where dangerous substances are used. By installing a universal gas detector, you can bring your gas distribution plant in line with mandatory requirements to keep workers safe on the job.

Not all gas monitors are created equal. It's important to choose a gas monitor that is flexible, especially if you work with a range of substances, and reliable for continuous operation. Gas monitors that do not take accurate readings place worker health at risk, because they may fail to spot a low-level leak.

PureAire's universal gas monitor detects a wide range of gases, including:

·        Ammonia

·        Chlorine

·        Fluorine

·        Hydrogen chloride

·        Hydrogen fluoride

·        Nitrogen dioxide

·        Phosphine

·        and more

PureAire's universal gas monitor is designed to function optimally once set up with no routine maintenance. The renewable sensor lasts for 3 to 8 years on average. Unlike other monitors, PureAire's sensor is rechargeable onsite, to save your gas storage facility time and money. While employees can check interface readouts for peace of mind, the gas detector works 24/7 out of the box. If the unit experiences a problem, error readouts are related to the control room.

Since the monitor has a built-in LCD display, employees can check substance levels at a glance. Dual level alarm relay contacts allow gas distributors to choose the appropriate level for their purposes. Alarms provide employees with sufficient notification to close valves, exit the area, and reduce the risk of fire.

PureAire is an industry leader with more than 15 years of experience developing oxygen monitors and universal gas detectors. Our products provide reliable reports to increase safety and peace of mind. Learn more about our universal gas monitor and view full product specifications online.

 https://www.pureairemonitoring.com/universal-gas-detector/

https://www.pureairemonitoring.com/paint-booths-or-areas-using-combustible-gases/

https://www.chemicalsafetyfacts.org/ammonia/