Carbon Dioxide: What are the dangers in the Food and Beverage Industry? 

Almost all industries must monitor gas hazards, with the food and beverage industry no exception. Although, there is a lack of awareness regarding the dangers of carbon dioxide (CO2) and the dangers those working in the industry face. CO2 is the most common gas in the food and beverage industry because it is used in the carbonation of drinks, to propel beverages to the tap in pubs and restaurants and to keep food items cold during transportation in the form of dry ice. It is also naturally produced in beverage manufacturing processes by leavening agents like yeast and sugar. Although CO2 may seem harmless at first glance as we exhale it with every breath, and plants need it for survival, the presence of carbon dioxide becomes a problem when its concentration rises to dangerous levels.

The Dangers of CO2

Carbon dioxide occurs naturally in the atmosphere (typically 0.04% in air). CO2 is colourless and odourless, heavier than air, and tends to sink to the floor. CO2 collects in cellars and at the bottom of containers and confined spaces such as tanks or silos.

Since CO2 is heavier than air, it quickly displaces oxygen at high concentrations can result in asphyxiation due to a lack of oxygen or breathable air. Exposure to CO2 is easy, especially in a confined space like a tank or a cellar. Early symptoms of exposure to high levels of carbon dioxide include dizziness, headaches, and confusion, followed by loss of consciousness. Accidents and fatalities occur in the food and beverage industry due to a carbon dioxide leak. Without proper detection methods and processes in place, everyone at a facility could be at risk.

Gas Monitors – what are the benefits?

Any application that uses carbon dioxide puts workers at risk, and the only way to identify high levels before it’s too late is to use gas monitors.

Gas detection can be provided in both fixed and portable forms. Installation of a fixed gas detector can benefit a larger space such as plant rooms to provide continuous area and staff protection 24 hours a day. However, a portable detector can be more suited for worker safety in and around the cylinder storage area and in spaces designated as a confined space. This is especially true for pubs and beverage dispensing outlets for the safety of workers and those unfamiliar with the environment, such as delivery drivers, sales teams or equipment technicians. The portable unit can easily be clipped to clothing and will detect pockets of CO2 using alarms and visual signals, indicating that the user should immediately vacate the area.

Personal gas detectors continuously monitor the air in workers’ breathing zone when worn correctly,  to give them better awareness and the information they need to make smart decisions in the face of danger. Not only can gas monitors detect carbon dioxide in the air, but they can also alert others if an employee is in danger. Carbon dioxide can be monitored using a single gas monitor or by using a multi-gas monitor with a dedicated carbon dioxide sensor. It is important to note the carbon dioxide can escalate to dangerous levels before an oxygen sensor would alarm.

What is IR Technology? 

Infrared emitters within the sensor each generate beams of IR light. Each beam is measured by a photo-receiver. The “measuring” beam, with a frequency of around 3.3μm, is absorbed by hydrocarbon gas molecules, so the beam intensity is reduced if there is an appropriate concentration of a gas with C-H bonds present. The “reference” beam (around 3.0μm) is not absorbed by gas, so arrives at the receiver at full strength. The %LEL of gas present is determined by the ratio of the beams measured by the photo-receiver. 

Benefits of IR technology 

IR sensors are reliable in some environments that can cause pellistor-based sensors to function incorrectly or in some cases fail. In some industrial environments, pellistors are at risk of being poisoned or inhibited. This would leave a worker on their shift unprotected. IR sensors are not susceptible to the catalyst poisons so significantly enhance safety in these conditions. 

Pellistor technology is considerably less expensive than IR technology, reflecting the comparative simplicity of the detection technology. However, there are several advantages of IR over pellistors. These include IR technology provides fail-safe testing. The mode of operation means that if the infrared beam failed, this would register as a fault.  In normal pellistor operation, conversely, a lack of output is ordinarily an indication that no flammable gas is present, but this could also be the result of a fault. Pellistors are susceptible to poisoning or inhibition; a particular concern in environments where compounds containing silicon, lead, sulphur and phosphates, even at low levels. IR instruments don’t, themselves, interact with the gas.  Only the IR beam interacts with the gas molecules, so, IR technology is immune to poisoning or inhibition by chemical toxins. In high concentrations of flammable gas, pellistor sensors can burn out. As with poisoning or inhibition, this would probably only be picked up by testing.  Again, IR sensors are not affected by these conditions. Low levels of oxygen mean that pellistor sensors won’t work. This can be the case in recently purged tanks, but also in confined spaces generally, where pellistors may be ineffective.  IR technology is effective in areas where oxygen may be reduced or absent. 

Factors that affect IR technology  

Exposure to high levels of flammable gas can cause “sooting” of pellistors, reducing their sensitivity and potentially leading to failure. Pellistors require oxygen to function, however, IR sensors can be relied on in applications such as fuel storage tanks where there is little or no oxygen, due to flushing with inert gas prior to maintenance, or which still contain high levels of fuel vapours. The fail-safe nature of IR sensors, which automatically alert you to any fault, provides an additional layer of safety. Gas-Pro IR measures in %LEL and has been certified for use in hazardous areas as defined by both ATEX/IECEx and UL. 

Knowing when the technology has failed  

IR sensors are reliable in environments that can cause pellistor-based sensors to function incorrectly or in some cases fail. In some industrial environments, pellistors are at risk of being poisoned or inhibited. This leaves workers on their shifts unprotected. IR sensors are not susceptible to these conditions, so significantly enhance safety. 

Problems with IR sensors 

IR sensors do not measure hydrogen, and they usually don’t measure acetylene, ammonia of some complex solvents either except for some specialist sensor types. 

If nothing is done to prevent it, moisture can build up inside IR sensors on the optics scattering the IR light and causing a fault.  

The fail-safe nature of IR sensors, which automatically alert you to any fault, provides an additional layer of safety, and this results in a fault if there isn’t enough light getting through the system e.g., if the light is being scattered form the beam. 

IR sensors have very high resistance to interference or inhibition by other gases and are suitable for both high gas concentrations and use in inert (oxygen free) backgrounds where catalytic pellistor sensors would perform poorly. 

Products  

Our portable products such as Our Gas-Pro IR and Triple Plus+ help customers to detect potentially explosive gases where traditional, “pellistor,” catalytic sensors will struggle – especially in low oxygen or ‘poisoning’ environments. And allow for the measurement of hydrocarbons at both % LEL and % Volume ranges making this instrument ideal for tank and line purging applications. 

To explore more, visit our technical page for more information. 

Intrinsic Safety – What does it mean? 

Intrinsic safety is an explosion prevention technique used to ensure safe operation of electrical equipment in a hazardous area. This technique uses a low-energy signalling technique that reduces the energy within the equipment to below that required to initiate an explosion, whilst maintaining an energy level this is an be used for its operation.  

What is a hazardous area? 

A hazardous or explosion-prone relates to an environment that has vast amounts of flammable substances such as combustible particles, gases, vapor. Hazardous industrial areas include oil refineries, mining, distilleries and chemical plants. The main safety issue in these industrial scenarios is that of flammable vapours and gases. This is because when they are mix with oxygen within the air, they can establish an explosion-prone environment. Food processing factories, grain handling facilities, recycling operations, and even flour mills generate combustible dust, which is why these are classed as too hazardous locations. Hazardous places are classified in terms of zones on the basis of the frequency and duration of the occurrence of an explosive atmosphere. Areas subject to flammable gas hazards are classified as either Zone 0, Zone 1 or Zone 2. 

How does it work? 

Intrinsic safety prevents sparks and heat from being generated from any electrical equipment, devices or instruments that otherwise ay have initiated an explosion in a hazardous area. Hazardous spaces may belong, but are not limited to, to the following: petrochemical refineries, mines, agriculture grain storage, wastewater, distilling, pharmaceutical, brewing, and utilities. 

Intrinsic safety is achieved with the use of a Zener Diodes which limits voltage, resistors that limit the current and a fuse to cut off electricity. Equipment or devices that may be made intrinsically safe must first be approved for use in an intrinsically safe system through a competent authority, such as the National Fire Protection Agency (NFPA), the Canadian Standards Association (CSA), Underwriters Laboratories (UL), Factory Mutual (FM), National Electric Code (NEC), and the Instrument Society of Measurement and Control (ISA). 

The advantages of Intrinsic Safety 

The main advantage is that it provides a solution to all problems that occur in a hazardous area regarding equipment. It prevents the cost and bulk of explosion proof enclosures, with additional cost savings as a result of the ability to use standard instrumentation cables. Additionally, the maintenance and diagnostic work can be performed without shutting down production and ventilating the work area. 

Levels of protection  

Intrinsic safety relates to three levels of protection, ‘ia’, ‘ib’ and ‘ic’ that aim to balance the probability of an explosive atmosphere, assessing the probability of whether that is an ignition capable situation that may occur. 

‘ia’  

Offers the highest level of protection and any equipment that is given this level is generally considered adequately safe for use in the most hazardous locations (Zone 0) with two faults.  

‘ib’  

This level is considered adequately safe with one fault is considered safe for use in less frequently hazardous areas (Zone 1).  

‘ic’  

This level is given for ‘normal operation’ with a unity factor of safety is generally acceptable in infrequently hazardous areas (Zone 2). 

Level of protection 
Countable faults 
ATEX Category 
Normal Zone of use 
ia 2 1 0
ib 1 2 1
ic 0 3 2

 

To note, although it is normal for a whole system to be allocated a level of protection, it is also possible for different parts of the system to have different levels of protection.  

World Hydrogen Summit 2022

Crowcon exhibited at the World Hydrogen Summit & Exhibition 2022 on the 9th – 11th May 2022 as part of the event designed to advance development in the hydrogen sector. Based in Rotterdam and produced by the Sustainable Energy Council (SEC), this year’s exhibition was the first Crowcon has attended. We were excited to be part of an occasion which fosters connections and collaboration between those at the forefront of the heavy industry and drives the hydrogen sector forward.

Our team representatives met various industry peers and showcased our Hydrogen solutions for gas detection. Our MPS sensor offers a higher standard of flammable gas detection thanks to its pioneering advanced molecular property spectrometer (MPS™) technology that can detect and accurately identify over 15 different flammable gases. This showcased an ideal solution for hydrogen detection due to hydrogen having proprieties that allow for easy ignition and higher burn intensity compared to that of petrol or diesel, therefore poses a real explosion risk. To find out more read our blog.

Our MPS technology had interest due to this not requiring calibration throughout the life cycle of the sensor, and detects flammable gases without the risk of poisoning or false alarms, thereby having a significant saving on total cost of ownership and reduce interaction with units, ultimately providing peace of mind and less risk for operators.

The Summit allowed us to understand the current state of the hydrogen market, including key players and current projects, allowing for potential developed a greater understanding of our product needs in order to play a major role in the future of hydrogen gas detection.

We look forward to attending next year!

Gold Mining: What gas detection do I need? 

How is gold mined?

Gold is a rare substance equating to 3 parts per billion of the earth’s outer layer, with most of the world’s available gold coming from Australia. Gold, like iron, copper and lead, is a metal. There are two primary forms of gold mining, including open-cut and underground mining. Open mining involves earth-moving equipment to remove waste rock from the ore body above, and then mining is conducted from the remaining substance. This process requires waste and ore to be struck at high volumes to break the waste and ore into sizes suitable for handling and transportation to both waste dumps and ore crushers. The other form of gold mining is the more traditional underground mining method. This is where vertical shafts and spiral tunnels transport workers and equipment into and out of the mine, providing ventilation and hauling the waste rock and ore to the surface.

Gas detection in mining

When relating to gas detection, the process of health and safety within mines has developed considerably over the past century, from morphing from the crude usage of methane wick wall testing, singing canaries and flame safety to modern-day gas detection technologies and processes as we know them. Ensuring the correct type of detection equipment is utilised, whether fixed or portable, before entering these spaces. Proper equipment utilisation will ensure gas levels are accurately monitored, and workers are alerted to dangerous concentrations within the atmosphere at the earliest opportunity.

What are the gas hazards and what are the dangers?

The dangers those working within the mining industry face several potential occupational hazards and diseases, and the possibility of fatal injury. Therefore, understanding the environments and hazards, they may be exposed to is important.

Oxygen (O2)

Oxygen (O2), usually present in the air at 20.9%, is essential to human life. There are three main reasons why oxygen poses a threat to workers within the mining industry. These include oxygen deficiencies or enrichment, as too little oxygen can prevent the human body from functioning leading to the worker losing consciousness. Unless the oxygen level can be restored to an average level, the worker is at risk of potential death. An atmosphere is deficient when the concentration of O2 is less than 19.5%. Consequently, an environment with too much oxygen is equally dangerous as this constitutes a greatly increased risk of fire and explosion. This is considered when the concentration level of O2 is over 23.5%

Carbon Monoxide (CO)

In some cases, high concentrations of Carbon Monoxide (CO) may be present. Environments that this may occur include a house fire, therefore the fire service are at risk of CO poisoning. In this environment there can be as much as 12.5% CO in the air which when the carbon monoxide rises to the ceiling with other combustion products and when the concentration hits 12.5% by volume this will only lead to one thing, called a flashover. This is when the whole lot ignites as a fuel. Apart from items falling on the fire service, this is one of the most extreme dangers they face when working inside a burning building. Due to the characteristics of CO being so hard to identify, I.e., colourless, odourless, tasteless, poisonous gas, it may take time for you to realise that you have CO poisoning. The effects of CO can be dangerous, this is because CO prevents the blood system from effectively carrying oxygen around the body, specifically to vital organs such as the heart and brain. High doses of CO, therefore, can cause death from asphyxiation or lack of oxygen to the brain. According to statistics from the Department of Health, the most common indication of CO poisoning is that of a headache with 90% of patients reporting this as a symptom, with 50% reporting nausea and vomiting, as well as vertigo. With confusion/changes in consciousness, and weakness accounting for 30% and 20% of reports.

Hydrogen sulphide (H2S)

Hydrogen sulphide (H2S) is a colourless, flammable gas with a characteristic odour of rotten eggs. Skin and eye contact may occur. However, the nervous system and cardiovascular system are most affected by hydrogen sulphide, which can lead to a range of symptoms. Single exposures to high concentrations may rapidly cause breathing difficulties and death.

Sulphur dioxide (SO2)

Sulphur dioxide (SO2) can cause several harmful effects on the respiratory systems, in particular the lung. It can also cause skin irritation. Skin contact with (SO2) causes stinging pain, redness of the skin and blisters. Skin contact with compressed gas or liquid can cause frostbite. Eye contact causes watering eyes and, in severe cases, blindness can occur.

Methane (CH4)

Methane (CH4) is a colourless, highly flammable gas with a primary component being that of natural gas. High levels of (CH4) can reduce the amount of oxygen breathed from the air, which can result in mood changes, slurred speech, vision problems, memory loss, nausea, vomiting, facial flushing and headache. In severe cases, there may be changes in breathing and heart rate, balance problems, numbness, and unconsciousness. Although, if exposure is for a longer period, it can result in fatality.

Hydrogen (H2)

Hydrogen Gas is a colourless, odourless, and tasteless gas which is lighter than air. As it is lighter than air this means it float higher than our atmosphere, meaning it is not naturally found, but instead must be created. Hydrogen poses a fire or explosion risk as well as an inhalation risk. High concentrations of this gas can cause an oxygen-deficient environment. Individuals breathing such an atmosphere may experience symptoms which include headaches, ringing in ears, dizziness, drowsiness, unconsciousness, nausea, vomiting and depression of all the senses

Ammonia (NH3)

Ammonia (NH3) is one of the most widely used chemicals globally that is produced both in the human body and in nature. Although it is naturally created (NH3) is corrosive which poses a serve concern for health. High exposure within the air can result in immediate burning to the eyes, nose, throat and respiratory tract. Serve cases can result in blindness.

Other gas risks

Whilst Hydrogen Cyanide (HCN) doesn’t persist within the environment, improper storage, handling and waste management can pose severe risk to human health as well as effects on the environment. Cyanide interferes with human respiration at cellular levels that can cause serve and acute effects, including rapid breathing, tremors, asphyxiation.

Diesel particulate exposure can occur in underground mines as a result of diesel-powered mobile equipment used for drilling and haulage. Although control measures include the use of low sulphur diesel fuel, engine maintenance and ventilation, health implication includes excess risk of lung cancer.

Products that can help to protect yourself

Crowcon provide a range of gas detection including both portable and fixed products all of which are suitable for gas detection within the mining industry.

To find out more visit our industry page here.

Our Partnership with Hatech Gasdetectietechniek B.V.

Service providers are vital in supplying products and solution services to customers. However, they also provide customers with a range of knowledge and expertise to ensure they supply their customers with the correct equipment.

Background

Founded in 1994 and located in Raamsdonksveer, North Brabant, Hatech Gasdetectietechniek B.V. are a gas detection specialist. With over 25 years of experience, Hatech is the biggest service provider in the Netherlands, operating as a seven-person organisation and supply gas detection for the office, workshop, factory, plants, offshore, biogas or any other industrial environment. Hatech supply a wide range of gas detection products, from portable devices to complete fixed setups and customised installations. In addition to the supply of gas detection, Hatech is also a ‘one-stop shop’ as they issue calibration, service and supply rental of gas detection equipment.

Views on Gas Detection

Gas detection is a crucial piece of safety equipment for those who work in hazardous environments; therefore, supplying the correct equipment for the job is vital. Hatech ensures they provide the knowledge and understanding to enable their customers to understand and know the equipment they are buying correctly. Hatech issues tailor-made advice that ensures they know what application and who will be entering these environments to ensure that they offer the most suitable solution for your gas detection application.

Working with Crowcon

A 15-year partnership and continued communication have allowed Hatech to supply their customers with a gas detection solution. Although Hatech Gasdetectietechniek is based in the Netherlands, our partnership provides them with a short lead time allowing for a quick turnaround in products. Hatech is an official service centre for portable devices and supplying service engineers for fixed products. “Crowcon detectors are a premier gas detection solution that is simple to operate, with a complete sales and service team. Our partnership has provided our customers with new technology and the knowledge and understanding allowing for the correct equipment for the right application.”

T4x a Compliance 4-gas monitor 

It is vital to ensure that the gas sensor you employ is fully optimised and reliable in the detection and accurate measurement of flammable gas and vapours, whatever environment or workplace it is within, is of the utmost importance. 

Fixed or portable? 

Gas detectors come in a range of different forms, most commonly they are known as fixed, portable or transportable, in which these devices are designed to meet the needs of the user and environment whilst protecting the safety of those within it.  

Fixed detectors are implemented as permanent fixtures within an environment to provide ongoing monitoring of plant and equipment. According to guidance from the Health and Safety Executive (HSE) these types of sensors are particularly helpful where there is the possibility of a leak into an enclosed or partially enclosed space which could lead to the accumulation of flammable gases. The International Gas Carrier Code (IGC Code) states that gas detection equipment should be installed to monitor the integrity of the environment that it is to monitor and should be tested in accordance with the recognised standards. This is to ensure that the fixed gas detection system operates effectively, timely and accurate calibration of the sensors is critical. 

Portable detectors normally come as a small, handheld device that can be used within smaller environments, confined spaces, to trace leaks or early warnings to the presence of flammable gas and vapour within hazardous areas. Transportable detectors are not handheld, but they are easily moved from place to place to act as a monitor ‘stand-in’ whilst a fixed sensor is undergoing maintenance. 

What is a compliance 4-gas monitor? 

Gas sensors are primarily optimised for detecting specific gases or vapours through design or calibration. It is desirable that a toxic gas sensor, for example one detecting carbon monoxide or hydrogen sulphide, provides an accurate indication of the target gas concentration rather than a response to another interfering compound. Personal safety monitors often combine several sensors for protecting the user against specific gas risks. However, a ‘Compliance 4-Gas monitor’ comprises sensors for measuring levels of carbon monoxide (CO) hydrogen sulphide (H2S), oxygen (O2) and flammable gases; normally methane (CH4) in one device.  

The T4x monitor with the ground-breaking MPS™ sensor is able to provide protection from CO, H2S, O2 risks with accurate measurement of multiple flammable gases and vapours utilising a basic methane calibration. 

Is there a need for a compliance 4-gas monitor? 

Many of the flammable gas sensors deployed in conventional monitors are optimized for detecting a specific gas or vapour through calibration but will respond to many other compounds. This is problematic and potentially dangerous as the gas concentration indicated by the sensor will not be accurate and may indicate a higher (or more dangerously) and lower concentration of gas/vapour than is present. With workers often potentially exposed to risks from multiple flammable gases and vapours within their workplace, it is incredibly important to ensure that they are protected through the implementation of an accurate and reliable sensor. 

How is the T4x portable 4-in-1 gas detector different? 

To ensure ongoing reliability and accuracy of the T4x detector. The detector utilises the  MPS™ (Molecular Property Spectrometry) Sensor functionality within its robust unit that provides a range of features to ensure safety. It offers protection against the four common gas hazards: carbon monoxide, hydrogen sulphide, flammable gases and oxygen depletion, whilst The T4x multi gas detector now comes with improved detection of pentane, hexane and other long chain hydrocarbons. It comprises a large single button and easy-to-follow menu system to enable ease of use for those wearing gloves, who’ve undergone minimal training. Tough, yet portable, the T4x detector features an integrated rubber boot and an optional clip-on filter that can be easily removed and replaced when needed. These features allow the sensors to remain protected even within the dirtiest environments, to ensure they can constant. 

A unique benefit to the T4x detector is that it ensures toxic gas exposure is calculated accurately throughout an entire shift, even if it is switched off momentarily, during a break or when travelling to another site. The TWA feature allows for uninterrupted and disrupted monitoring, So, when powering up, the detector begins again from zero, as if starting a new shift and ignores all previous measurements. The T4x allows the user the option to include previous measurements from within the correct time frame. The detector is not just reliable in terms of accurate detection and measurement of four gases, it is also dependable due to its battery life. It lasts for 18 hours and is useful for usage across multiple or longer shifts without requiring charging as regularly.  

During usage the T4 employs a handy ‘traffic light’ display offering constant visual assurance that it is operating soundly and conforming to the site bump test and calibration policy. The bright green and red Positive Safety LEDs are visible to all and, as a result, offer a quick, simple and comprehensive indication of the monitor’s status to both the user and others around them. 

T4x helps operations teams focus on more value adding tasks by reducing the number of sensor replacements by 75% and increasing sensor reliability. Through ensuring compliance across site T4x helps health and safety managers by eliminating the need to ensure each device is calibrated for the relevant flammable gas as it accurately detects 19 at once. Being poison resistant and with battery life doubled, operators are more likely to never be without a device. T4x reduces the 5-year total cost of ownership by over 25% and saves 12g of lead per detector which makes it much easier to recycle at the end of its life. 

Overall, through the combination of three sensors (including two new sensor technologies MPS and Long-life O2) within an already popular portable multi-gas detector. Crowcon allowed for the enhancement of safety, cost-effectiveness and efficiency of individual units and entire fleets. The new T4x offers longer life with a higher accuracy for gas hazard detection whilst providing a more sustainable build than ever before. 

Our Partnership with Tyco (Johnson Controls)

Background 

Johnson Controls has over 120 years’ experience in providing complete life safety to the oil and gas industries world-wide helping to provide 90% of the world’s top fifty oil and gas companies. Merging with Tyco in 2018 they now provide a full turn-key solution for the global marine and navy industries. The merge has allowed for the protection of over 80% of the vessels at sea for all types of assets and facilities including fixed and portable devices. Johnson Controls also supply gas detection to the renewable industry.

Views on Gas Detection 

Johnson Controls is uniquely positioned to offer comprehensive and integrated solutions for a wide range of proven products and systems across several industries and applications. Johnson Controls have a culture that focuses on innovation and continuous improvement which in turn helps to us to solve current challenges whilst constantly looking to ‘What’s next’. As gas detection is an essential instrument for many workers within the oil and gas and marine industries, providing honestly and transparency is key as well as upholding the highest standards of integrity and honour in the commitments they make, ensure that their customers are given a solution that not only solves their pain but also protects their workers.  

Working with Crowcon 

Through continuous communication, our partnership with Johnson Controls has allowed them to provide honesty and transparency to their customers. This partnership has allowed Johnson Controls to reach a variety of industries and applications. Although previously our partnership has predominately been focused on our portable product range, future hopes will be focussed on our fixed product range, of which will allow Johnson Controls to expand their customer base as well as providing a solution to a wider audience. “Our partnership with Crowcon has allowed us to offer a solution to all customers, ensuring that those who we supply equipment to are protected.”  

Service, calibration and hire

With 25 years’ experience, Johnson Controls are experts in the service and calibration of our products in both their Aberdeen and Great Yarmouth offices. Johnson controls understand the need for gas detection therefore a fast turnaround is a must. Johnson controls not only distributes, services and calibrate our products but they also offer portable product hire in both locations.

What causes Hydrocarbon Fires?  

Hydrocarbon fires are caused by fuels containing carbon being burned in oxygen or air. Most fuels contain significant levels of carbon, including paper, petrol, and methane – as examples of solid, liquid or gaseous fuels – hence hydrocarbon fires. 

For there to be an explosion risk there needs to be at least 4.4% methane in air or 1.7% propane, but for solvents as little as 0.8 to 1.0% of the air being displaced can be enough to create a fuel air mix that will explode violently on contact with any spark.

Dangers associated with hydrocarbon fires

Hydrocarbon fires are considered highly dangerous when compared to fires that have ignited as a result of simple combustibles, as these fires have the capacity to burn at a larger scale as well as also having the potential to trigger an explosion if the fluids released cannot be controlled or contained. Therefore, these fires pose a dangerous threat to anyone who works in a high-risk area, the dangers include energy related dangers such as burning, incineration of surrounding objects. This is a danger due to the ability that the fires can grow quickly, and that heat can be conducted, converted and radiated to new sources of fuel causing secondary fires. 

Toxic hazards may be present in combustion products, for example, carbon monoxide (CO), hydrogen cyanide (HCN), hydrochloric acid (HCL), nitrogen dioxide (NO2) and various polycyclic aromatic hydrocarbons (PAH) compounds are dangerous for those working in these environments. CO uses the oxygen that is used to transport the red blood cells around the body, at least temporarily, impairing the body’s ability to transport oxygen from our lungs to the cells that need it. HCN adds to this problem by inhibiting the enzyme that tells the red blood cells to let go of the oxygen they have where it is needed – further inhibiting the body’s ability to get the oxygen to the cells that need it. HCL is a generally an acidic compound that is created through overheated cables. This is harmful to the body if ingested as it affects the lining of the mouth, nose, throat, airways, eyes, and lungs. NO2 is created in high temperature combustion and that can cause damage to the human respiratory tract and increase a person’s vulnerability to and in some cases lead to asthma attacks. PAH’s affects the body over a longer period of time, with serve cases leading to cancers and other illnesses. 

We can look up the relevant health levels accepted as workplace safety limits for healthy workers within Europe and the permissible exposure limits for the United States. This gives us a 15-minute time weighted average concentration and an 8-hour time weighted average concentration. 

For the gases these are: 

Gas  STEL (15-minute TWA)  LTEL (8-hour TWA)  LTEL (8hr TWA) 
CO  100ppm  20ppm  50ppm 
NO2  1ppm  0.5ppm  5 Ceiling Limit 
HCL  1ppm  5ppm  5 Ceiling Limit 
HCN  0.9ppm  4.5ppm  10ppm 

The different concentrations represent the different gas risks, with lower numbers needed for more dangerous situations. Fortunately, the EU has worked it all out for us and turned it into their EH40 standard. 

Ways of protecting ourselves

We can take steps to ensure we do not suffer from exposure to fires or their unwanted combustion products. Firstly of course, we can adhere to all fire safety measures, as is the law. Secondly, we can take a pro-active approach and not let potential fuel sources accumulate. Lastly, we can detect and warn of the presence of combustion products using appropriate gas detection equipment. 

Crowcon product solutions

Crowcon provides a range of equipment capable of detecting fuels and the combustion products described above. Our PID products detect solids and liquid-based fuels once they are airborne, as either hydrocarbons on dust particles or solvent vapours. This equipment includes our GasPro portable. The gases can be detected by our Gasman single gas, T3 multi gas and Gas-Pro multi gas pumped portable products, and our Xgard, Xgard Bright and Xgard IQ fixed products – each of which has the capability of detecting all the gases mentioned. 

The importance of Gas Detection in the Waste to Energy industry 

Waste is composed of materials that are no longer needed, and thus are discarded. Waste can be classified as solid or liquid according to its form, and further categorised as hazardous and non-hazardous waste. Liquid waste includes municipal wastewater, storm water run-off and industrial wastewater discharge. 

Solid waste includes household rubbish, which is also called municipal solid waste (MSW), industrial waste – for example, from agriculture – medical and electronics waste. 

The treatment of solid waste is challenging because it may contain one of more contaminants (which may include heavy metals, explosive and flammable materials) and these must be dealt with before the waste can be treated. 

What are the gas hazards? 

There are many processes to turn waste into energy, these include, biogas plants, refuse collection, leachate pool, combustion and heat recovery, exhaust air scrubber and ash pit. All these processes pose gas hazards to those working in these environments.  

Within a Biogas Plant, biogas is produced. This is formed when organic materials such as agricultural and food waste are broken down by bacteria in an oxygen-deficient environment. This is a process called anaerobic digestion. When the biogas has been captured, it can be used to produce heat and electricity for engines, microturbines and fuel cells. Clearly, biogas has high methane content as well as substantial hydrogen sulphide (H2S), and this generates multiple serious gas hazards. (Read our blog for more information on biogas). However, there is an elevated risk of, fire and explosion, confined space hazards, asphyxiation, Oxygen depletion and gas poisoning (H2S, ammonia (NH3)). Workers in a biogas plant must have personal gas detectors that detect and monitor flammable gas, oxygen and toxic gases like H2S and carbon monoxide (CO).

Within a refuse collection it is common to find flammable gas methane (CH4) and toxic gases H2S, CO and NH3. This is because refuse bunkers are built several metres underground and gas detectors are usually mounted high above them, this makes those detectors hard to service and calibrate. In many cases, a sampling system is a practical solution as air samples can be brought to a convenient location and measured.

Leachate is a liquid that drains (leaches) from an area in which waste is collected, with leachate pools presenting a range of gas hazards. These include the risk of flammable gas (explosion risk), H2S (poison, corrosion), ammonia (poison, corrosion), CO (poison) and adverse oxygen levels (suffocation). Leachate pool and passageways leading to the leachate pool requiring monitoring of CH4, H2S, CO, NH3, oxygen (O2) and carbon dioxide (CO2). Various gas detectors should be placed along routes to the leachate pool, with output connected to external control panels.

Combustion and heat recovery requires the detection of O2 and toxic gases sulphur dioxide (SO2) and CO. These gases all pose a threat to those who work in boiler house areas.

Another process that is classed as a gas hazard is an exhaust air scrubber. The process is hazardous as the flue gas from incineration is highly toxic. This is because it contains pollutants such as nitrogen dioxide (NO2), SO2, hydrogen chloride (HCL) and dioxin. NO2 and SO2 are major greenhouse gases, while HCL and dioxides are harmful to human health.

Additionally, ash pits contain toxic gases as well as oxygen monitoring, through both O2 and CO.  

To read more on the waste to energy industry, visit our industry page.