The importance of gas detection in the Medical and Healthcare sector

The need for gas detection in the medical and healthcare sector may be less widely understood outside of the industry, but the requirement is there, nonetheless. With patients across a number of settings receiving a variety of treatment and medical therapies that involve the usage of chemicals, the need to accurately monitor the gases utilised or emitted, within this process is very important to allow for their continued safe treatment. In order to safeguard both patients and, of course, the healthcare professionals themselves, the implementation of accurate and reliable monitoring equipment is a must.

Applications

In healthcare and hospital settings, a range of potentially hazardous gases can present themselves due to the medical equipment and apparatus utilised. Harmful chemicals are also used for disinfectant and cleansing purposes within hospital work surfaces and medical supplies. For example, potentially hazardous chemicals can be used as a preservative for tissue specimens, such as toluene, xylene or formaldehyde. Applications include:

  • Breath gas monitoring
  • Chiller rooms
  • Generators
  • Laboratories
  • Storage rooms
  • Operating theatres
  • Pre-hospital rescue
  • Positive airway pressure therapy
  • High flow nasal cannula therapy
  • Intensive care units
  • Post anaesthesia care unit

Gaz Hazards

Oxygen Enrichment in Hospital Wards

In light of the worldwide pandemic, COVID-19, the need for increased oxygen on hospital wards has been recognised by healthcare professionals due to the escalating number of ventilators in use. Oxygen sensors are vital, within ICU wards specifically, as they inform the clinician how much oxygen is being delivered to the patient during ventilation. This can prevent the risk of hypoxia, hypoxemia or oxygen toxicity. If oxygen sensors do not function as they should; they can alarm regularly, need changing and unfortunately even lead to fatalities. This increased use of ventilators also enriches the air with oxygen and can raise the combustion risk. There is a need to measure the levels of oxygen in the air using a fixed gas detection system to avoid unsafe levels in the air.

Carbon Dioxide

Carbon dioxide level monitoring is also required in healthcare environments to ensure a safe working environment for professionals, as well as to safeguard patients being treated. Carbon dioxide is used within a plethora of medical and healthcare procedures from minimally invasive surgeries, such as endoscopy, arthroscopy and laparoscopy, cryotherapy and anaesthesia. CO2 is also used in incubators and laboratories and, as it is a toxic gas, can cause asphyxiation. Heightened levels of CO2 in the air, emitted by certain machinery, can cause harm to those in the environment, as well as spread pathogens and viruses. CO2 detectors in healthcare environments can therefore improve ventilation, air flow and the wellbeing of all.

Volatile Organic Compounds (VOCs)

A range of VOCs can be found in hospital and healthcare environments and cause harm to those working and being treated within it. VOCs such as aliphatic, aromatic and halogenated hydrocarbons, aldehydes, alcohols, ketones, ethers and terpenes, to name a few, have been measured in hospital environments, originating from a number of specific areas including reception halls, patient rooms, nursing care, post-anaesthesia care units, parasitology-mycology labs and disinfection units. Although still in the research stage of their prevalence in healthcare settings, it is clear VOC ingestion has adverse effects on human health such as irritation to the eyes, nose, and throat; headaches and the loss of coordination; nausea; and damage to the liver, kidneys, or central nervous system. Some VOCs, benzene specifically, is a carcinogen. Implementing gas detection is therefore a must to safeguard everyone from harm.

Gas sensors should therefore be used within PACU, ICU, EMS, pre-hospital rescue, PAP therapy and HFNC therapy to monitor the gas levels of a range of equipment including ventilators, oxygen concentrators, oxygen generators and anaesthesia machines.

Standards and Certifications

The Care Quality Commission (CQC) is the organisation in England that regulates the quality and safety of the care delivered within all healthcare, medical, health and social care, and voluntary care settings across the country. The commission provides best practice details for the administering of oxygen to patients and the proper measurement and recording of levels, storage and training about the use of this and other medical gases.

The UK regulator for medical gases is the Medicines and Healthcare products Regulatory Agency (MHRA). They are an Executive Agency of the Department of Health and Social Care (DHSC) that ensures public and patient health and safety through the regulation of medicines, healthcare products and medical equipment in the sector. They set appropriate standards of safety, quality, performance and effectiveness, and ensure all equipment is used safely. Any company manufacturing medical gases requires a Manufacturer’s Authorisation issued by the MHRA.

In the USA The Food and Drug Association (FDA) regulates the certification process for the manufacture, sale and marketing of designated medical gases. Under Section 575 the FDA states that anyone marketing a medical gas for human or animal drug use without an approved application is breaking specified guidelines. The medical gases that require certification include oxygen, nitrogen, nitrous oxide, carbon dioxide, helium, 20 carbon monoxide, and medical air.

To find out more on the dangers in the medial and healthcare sector, visit our industry page for more information.

Why is gas detection crucial for drink dispense systems

Dispense gas known as beer gas, keg gas, cellar gas or pub gas is used in bars and restaurants as well as the leisure and hospitality industry. Using dispense gas in the process of dispensing beer and soft drinks is common practice worldwide. Carbon dioxide (CO2) or a mix of CO2 and nitrogen (N2) is used as a way of delivering a beverage to the ‘tap’. CO2 as a keg gas helps to keep the contents sterile and at the right composition aiding dispensing.

Gas Hazards

Even when the beverage is ready to deliver, gas-related hazards remain. Those arise in any activity at premises that contain compressed gas cylinders, due to the risk of damage during their movement or replacement. Additionally, once released there is a risk of increased carbon dioxide levels or depleted oxygen levels (due to higher levels of nitrogen or carbon dioxide).

CO2 occurs naturally in the atmosphere (0.04%) and is colourless and odourless. It is heavier than air and if it escapes, will tend to sink to the floor. CO2 collects in cellars and at the bottom of containers and confined spaces such as tanks and silos. CO2 is generated in large amounts during fermentation. It is also injected into beverages during carbonation – to add the bubbles. Early symptoms of exposure to high levels of carbon dioxide include dizziness, headaches, and confusion, followed by loss of consciousness. Accidents and fatalities can occur in extreme cases where a significant amount of carbon dioxide leaks into an enclosed or poorly ventilated volume. Without proper detection methods and processes in place, everyone entering that volume could be at risk. Additionally, personnel within surrounding volumes could suffer from the early symptoms listed above.

Nitrogen (N2) is often used in the dispensing of beer, particularly stouts, pale ales and porters, it also as well as preventing oxidisation or pollution of beer with harsh flavours. Nitrogen helps push the liquid from one tank to another, as well as offer the potential to be injected into kegs or barrels, pressurising them ready for storage and shipment. This gas is not toxic, but does displace oxygen in the atmosphere, which can be a danger if there is a gas leak which is why accurate gas detection is critical.

As nitrogen can deplete oxygen levels, oxygen sensors should be used in environments where any of these potential risks exist. When locating oxygen sensors, consideration needs to be given to the density of the diluting gas and the “breathing” zone (nose level). Ventilation patterns must also be considered when locating sensors. For example, if the diluting gas is nitrogen, then placing the detection at shoulder height is reasonable, however if the diluting gas is carbon dioxide, then the detectors should be placed at knee height.

The Importance of Gas Detection in Drinks Dispense Systems

Unfortunately, accidents and fatalities do occur in the drinks industry due to gas hazards. As a result, in the UK, safe workplace exposure limits are codified by the Health and Safety Executive (HSE) in documentation for the Control of Substances Hazardous to Health (COSHH). Carbon dioxide has an 8-hour exposure limit of 0.5% and a 15-minute exposure limit of 1.5% by volume. Gas detection systems help to mitigate gas risks and allow for drinks manufacturers, bottling plants and bar/pub cellar owners, to ensure the safety of personnel and demonstrate compliance to legislative limits or approved codes of practice.

Oxygen Depletion

The normal concentration of oxygen in the atmosphere is approximately 20.9% volume. Oxygen levels can be dangerous if they are too low (oxygen depletion). In the absence of adequate ventilation, the level of oxygen can be reduced surprisingly quickly by breathing and combustion processes.

Oxygen levels may also be depleted due to dilution by other gases such as carbon dioxide (also a toxic gas), nitrogen or helium, and chemical absorption by corrosion processes and similar reactions. Oxygen sensors should be used in environments where any of these potential risks exist. When locating oxygen sensors, consideration needs to be given to the density of the diluting gas and the “breathing” zone (nose level). Oxygen monitors usually provide a first-level alarm when the oxygen concentration has dropped to 19% volume. Most people will begin to behave abnormally when the level reaches 17%, and hence a second alarm is usually set at this threshold. Exposure to atmospheres containing between 10% and 13% oxygen can bring about unconsciousness very rapidly; death comes very quickly if the oxygen level drops below 6% volume.

Our Solution

Gas detection can be provided in the form of both fixed and portable detectors. Installation of a fixed gas detector can benefit a larger space such as cellars or plant rooms to provide continuous area and staff protection 24 hours a day. However, for worker safety in and around cylinder storage area and in spaces designated as a confined space, a portable detector can be more suited. This is especially true for pubs and beverage dispensing outlets for the safety of workers and those who are unfamiliar in 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 COusing alarms and visual signals, indicating that the user should immediately vacate the area.

For more information about gas detection in drink dispense systems, contact our team.

The importance of Gas Detection in the Water and Wastewater Industry 

Water is vital to our daily lives, both for personal and domestic use and industrial/commercial applications. Whether a facility focuses on the production of clean, potable water or treating effluent, Crowcon is proud to serve a wide variety of water industry clients, providing gas detection equipment that keeps workers safe around the world. 

Gas Hazards 

Apart from common gas hazards known in the industry; methane, hydrogen sulphide, and oxygen, there are bi-product gas hazards and cleaning material gas hazards that occur from purifying chemicals such as ammonia, chlorine, chlorine dioxide or ozone that are used in the decontamination of the waste and effluent water, or to remove microbes from clean water. There is great potential for many toxic or explosive gases to exist as a result of the chemicals used in the water industry. And added to these are chemicals that may be spilled or dumped into the waste system from industry, farming or building work. 

Safety Considerations  

Confined Space Entry 

The pipelines used to transport water require regular cleaning and safety checks; during these operations, portable multi-gas monitors are used to protect the workforce. Pre-entry checks must be completed prior to entering any confined space and commonly O2, CO, H2S and CH4 are monitored. Confined spaces are small, so portable monitors must be compact and unobtrusive for the user, yet able to withstand the wet and dirty environments in which they must perform. Clear and prompt indication of any increase in gas monitored (or any decrease for oxygen) is of paramount importance – loud and bright alarms are effective in raising the alarm to the user. 

Risk assessment 

Risk assessment is critical, as you need to be aware of the environment that you are entering and thus working in. Therefore, understanding the applications and identifying the risks regarding all safety aspects. Focusing on gas monitoring, as part of the risk assessment, you need to be clear on what gases may be present.  

Fit for purpose 

There is a variety of applications within the water treatment process, giving the need to monitor multiple gases, including carbon dioxide, hydrogen sulphide, chlorine, methane, oxygen, ozone and chlorine dioxide. Gas detectors are available for single or multiple gas monitoring, making them practical for different applications as well as making sure that, if conditions change (such as sludge is stirred up, causing a sudden increase in hydrogen sulphide and flammable gas levels), the worker is still protected.  

Legislation   

European Commission Directive 2017/164 issued in January 2017, established a new list of indicative occupational exposure limit values (IOELVs). IOELV are health-based, non-binding values, derived from the most recent scientific data available and considering the availability of reliable measurement techniques. The list includes carbon monoxide, nitrogen monoxide, nitrogen dioxide, sulphur dioxide, hydrogen cyanide, manganese, diacetyl and many other chemicals. The list is based on Council Directive 98/24/EC that considers the protection of the health and safety of workers from the risks related to chemical agents in the workplace. For any chemical agent for which an IOELV has been set at Union level, Member States are required to establish a national occupational exposure limit value. They also are required to take into account the Union limit value, determining the nature of the national limit value in accordance with national legislation and practice. Member States will be able to benefit from a transitional period ending at the latest on 21 August 2023.  

The Health and Safety Executive (HSE) state that each year several workers will suffer from at least one episode of work-related illness. Although, most illnesses are relatively mild cases of gastroenteritis, there is also a risk for potentially fatal diseases, such as leptospirosis (Weil’s disease) and hepatitis. Even though these are reported to the HSE, there could be significant under-reporting as there is often failure to recognise the link between illness and work.  

Under domestic law of the Health and Safety at Work etc Act 1974, employers are responsible for ensuring the safety of their employees and others. This responsibility is reinforced by regulations. 

The Confined Spaces Regulations 1997 applies where the assessment identifies risks of serious injury from work in confined spaces. These regulations contain the following key duties: 

  • Avoid entry to confined spaces, e.g., by doing the work from the outside. 
  • If entry to a confined space is unavoidable, follow a safe system of work.
  • Put in place adequate emergency arrangements before the work start. 

The Management of Health and Safety at Work Regulations 1999 requires employers and self-employed people to carry out a suitable and sufficient assessment of the risks for all work activities for the purpose of deciding what measures are necessary for safety. For work in confined spaces this means identifying the hazards present, assessing the risks and determining what precautions to take. 

Our solutions

Elimination of these gas hazards is virtually impossible, so permanent workers and contractors must depend on reliable gas detection equipment to protect them. Gas detection can be provided in both fixed and portable forms. Our portable gas detectors protect against a wide range of gas hazards, these include T4x, Clip SGD, Gasman, Tetra 3,Gas-Pro, T4 and Detective+. Our fixed gas detectors are used in many applications where reliability, dependability and lack of false alarms are instrumental to efficient and effective gas detection, these include Xgard, Xgard Bright and IRmax. Combined with a variety of our fixed detectors, our gas detection control panels offer a flexible range of solutions that measure flammable, toxic and oxygen gases, report their presence and activate alarms or associated equipment, for the wastewater industry our panels include Gasmaster.    

To find out more on the gas hazards in wastewater and water treatment visit our industry page for more information.  

Construction and Key Gas Challenges

Workers in the construction industry are at risk from a wide variety of hazardous gases including Carbon Monoxide (CO), Chlorine Dioxide (CLO2), Methane (CH4), Oxygen (O2), Hydrogen Sulphide (H2S) and Volatile Organic Compounds (VOC’s). 

Through the use of specific equipment, transport and the undertaking of sector specific activities, construction is a main contributor to the emission of toxic gases into the atmosphere, which also means construction personnel are more at risk of ingestion of these toxic contaminants. 

Gas challenges can be found in a variety of applications including building material storage, confined spaces, welding, trenching, land clearing and demolition. Ensuring the protection of workers within the construction industry from the multitude of hazards they may encounter is very important. With a specific focus on safeguarding teams from harm by, or the consumption of, toxic, flammable and poisonous gases. 

Gas Challenges 

Confined Space Entry 

Workers are more at risk from hazardous gases and fumes when they are operating within confined spaces.  Those entering these spaces need to be protected from the presence of flammable or/and toxic gases such as Volatile Organic Compounds (ppm VOC), Carbon Monoxide (ppm CO) and Nitrogen Dioxide (ppm NO2). Undertaking clearance measurements and pre-entry safety checks are paramount to ensure safety before a worker enters the space. Whilst in confined spaces gas detection equipment must be worn ongoingly in case of environmental shifts which make the space no longer safe to work in, due to a leak for example, and evacuation is needed. 

Trenching and Shoring 

During excavation works, such as trenching and shoring, construction workers are at risk of inhaling harmful gases generated by degradable materials present in certain ground types. If undetected, as well as posing risks to the construction workforce, they can also migrate through subsoil and cracks into the completed building and harm housing residents. Trenched areas can also have reduced oxygen levels, as well as contain toxic gases and chemicals. In these cases atmospheric testing should be performed in excavations that exceed four feet. There is also the risk of hitting utility lines when digging which can cause natural gas leaks and lead to worker fatalities. 

Building Material Storage  

Many of the materials used within construction can release toxic compounds (VOC’s). These can form in a variety of states (solid or liquid) and come from materials such as adhesives, natural and plywood’s, paint, and building partitions. Pollutants include phenol, acetaldehyde and formaldehyde. When ingested, workers can suffer from nausea, headaches, asthma, cancer and even death. VOCs are specifically dangerous when consumed within confined spaces, due to the risk of asphyxiation or explosion. 

Welding and Cutting 

Gases are produced during the welding and cutting process, including carbon dioxide from the decomposition of fluxes, carbon monoxide from the breakdown of carbon dioxide shielding gas in arc welding, as well as ozone, nitrogen oxides, hydrogen chloride and phosgene from other processes. Fumes are created when a metal is heated above its boiling point and then its vapours condense into fine particles, known as solid particulates. These fumes are obviously a hazard for those working in the sector and  illustrate the importance of reliable gas detection equipment to reduce exposure. 

Health and Safety Standards 

Organisations working in the construction sector can prove their credibility and safety operationally by gaining ISO certification. ISO (International Organisation for Standardisation) certification is split across multiple different certificates, all of which recognise varying elements of safety, efficiency and quality within an organisation. Standards cover best practice across safety, healthcare, transportation, environmental management and family. 

Although not a legal requirement, ISO standards are widely recognised as making the construction industry a safer sector by establishing global design and manufacturing definitions for almost all processes. They outline specifications for best practice and safety requirements within the construction industry from the ground up. 

In the UK, other recognised safety certifications include the NEBOSH, IOSH and CIOB courses which all offer varied health and safety training for those in the sector to further their understanding of working safely in their given field.  

To find out more on the gas challenges in construction visit our industry page for more information. 

Gas Hazards in Wastewater

Water is vital to our daily lives, both for personal and domestic use and industrial/commercial applications making water sites both numerous and widespread. Despite the quantity and location of water sites, only two environments predominate, and these are quite specific. They are clean water and wastewater. This blog details gas risks encountered at wastewater sites and how they may be mitigated. 

The wastewater industry is always wet, with temperatures between 4 and 20oc near the water and rarely far from that limited temperature range even away from the immediate location of the wastewater. 90%+ relative humidity, 12 +/- 8oc, atmospheric pressure, with multiple toxic and flammable gas hazards and the risk of oxygen depletion. Gas detectors must be chosen to suit the specific environment in which they operate, and whilst high humidity is generally challenging to all instrumentation, the constant pressure, moderate temperatures and narrow temperature range is a far greater benefit to safety instrumentation. 

Gas Hazards  

The main gases of concern in wastewater treatment plants are: 

  • Methane 
  • Hydrogen sulphide 
  • Carbon dioxide  
  • Reduced levels of oxygen 

Hydrogen sulphide, methane and carbon dioxide are the by-products of the decomposition of organic materials that exist in the waste flows feeding the plant. The build-up of these gases may lead to the lack of oxygen, or in some cases, explosion when coupled with a source of ignition. 

Hydrogen sulphide (H2S)

Hydrogen sulphide is a common product of the biodegradation of organic matter; pockets of H2S can collect in rotting vegetation, or sewage itself, and be released when disturbed. Workers in sewerage and wastewater plants and pipework can be overcome by H2S, with fatal consequences. Its high toxicity is the main danger of H2S. Prolonged exposure to 2-5 parts per million (ppm) H2S can cause nausea and headaches and bring tears to the eyes. H2S is an anaesthetic, hence at 20ppm, symptoms include fatigue, headaches, irritability, dizziness, temporary loss of the sense of smell and impaired memory. Severity of symptoms increase with concentration as nerves shut down, through coughing, conjunctivitis, collapse and rapid unconsciousness. Exposure at higher levels can result in rapid knock down and death. Prolonged exposure to low levels of H2S may cause chronic illness or can also kill. Because of this, many gas monitors will have both instantaneous and TWA (Time-Weighted Average) alerts. 

Methane (CH4)

Methane is a colourless, highly flammable gas that is the primary component of natural gas, also referred to as biogas. It can be stored and/or transported under pressure as a liquid-gas. CH4 is a greenhouse gas that is also encountered in normal atmospheric conditions at a rate of approximately 2 parts per million (ppm). High exposure can lead to slurred speech, vision problems and memory loss. 

Oxygen (O2)

The normal concentration of oxygen in the atmosphere is approximately 20.9% volume. In the absence of adequate ventilation, the level of oxygen can be reduced surprisingly quickly by breathing and combustion processes. Olevels may also be depleted due to dilution by other gases such as carbon dioxide (also a toxic gas), nitrogen or helium, and chemical absorption by corrosion processes and similar reactions. Oxygen sensors should be used in environments where any of these potential risks exist. When locating oxygen sensors, consideration needs to be given to the density of the diluting gas and the “breathing” zone (nose level). 

Safety Considerations 

Risk assessment

Risk assessment is critical, as you need to be aware of the environment that you are entering and thus working in. Therefore, understanding the applications and identifying the risks regarding all safety aspects. Focusing on gas monitoring, as part of the risk assessment, you need to be clear on what gases may be present. 

Fit for purpose

There is a variety of applications within the water treatment process, giving the need to monitor multiple gases, including carbon dioxide, hydrogen sulphide, chlorine, methane, oxygen, ozone and chlorine dioxide. Gas detectors are available for single or multiple gas monitoring, making them practical for different applications as well as making sure that, if conditions change (such as sludge is stirred up, causing a sudden increase in hydrogen sulphide and flammable gas levels), the worker is still protected. 

Legislation  

European Commission Directive 2017/164 issued in January 2017, established a new list of indicative occupational exposure limit values (IOELVs). IOELV are health-based, non-binding values, derived from the most recent scientific data available and considering the availability of reliable measurement techniques. The list includes carbon monoxide, nitrogen monoxide, nitrogen dioxide, sulphur dioxide, hydrogen cyanide, manganese, diacetyl and many other chemicals. The list is based on Council Directive 98/24/EC that considers the protection of the health and safety of workers from the risks related to chemical agents in the workplace. For any chemical agent for which an IOELV has been set at Union level, Member States are required to establish a national occupational exposure limit value. They also are required to take into account the Union limit value, determining the nature of the national limit value in accordance with national legislation and practice. Member States will be able to benefit from a transitional period ending at the latest on 21 August 2023. 

The Health and Safety Executive (HSE) state that each year several workers will suffer from at least one episode of work-related illness. Although, most illnesses are relatively mild cases of gastroenteritis, there is also a risk for potentially fatal diseases, such as leptospirosis (Weil’s disease) and hepatitis. Even though these are reported to the HSE, there could be significant under-reporting as there is often failure to recognise the link between illness and work. 

Our solutions  

Elimination of these gas hazards is virtually impossible, so permanent workers and contractors must depend on reliable gas detection equipment to protect them. Gas detection can be provided in both fixed and portable forms. Our portable gas detectors protect against a wide range of gas hazards, these include T4x, Clip SGD, Gasman, Tetra 3, Gas-Pro, T4 and Detective+. Our fixed gas detectors are used where reliability, dependability and lack of false alarms are instrumental to efficient and effective gas detection, these include Xgard, Xgard Bright and IRmax. Combined with a variety of our fixed detectors, our gas detection control panels offer a flexible range of solutions that measure flammable, toxic and oxygen gases, report their presence and activate alarms or associated equipment, for the wastewater industry our panels include Gasmaster.   

To find out more on the gas hazards in wastewater visit our industry page for more information. 

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.

Hydrogen Electrolysis

At present the most commercially developed technology available to produce hydrogen is from electrolysis. Electrolysis is an optimistic course of action for carbon-free hydrogen production from renewable and nuclear resources. Water electrolysis is the decomposition of water (H2O) into its basic components, hydrogen (H2) and oxygen (O2), through passing electric current. Water is a complete source for producing hydrogen and the only by-product released during process is oxygen. This process uses electrical energy that can then be stored as a chemical energy in the form of hydrogen.

What is the Process?

To produce Hydrogen, Electrolysis converts electrical energy into chemical energy by storing electrons in stable chemical bonds. Like fuel cells, electrolysers are composed of an anode and a cathode separated by an aqueous electrolyte according to the type of electrolyte material involved and the ionic species it conducts. The electrolyte is an obligatory part as pure water does not have the ability to carry enough charge as it lacks ions. At the anode, water is oxidised into oxygen gas and hydrogen ions. While the cathode, water is reduced to hydrogen gas and hydroxide ions. At present there are three leading electrolysis technologies.

Alkaline Electrolysers (AEL)

This technology has been used on an industrial scale for over 100 years. Alkaline electrolysers operate via transport of hydroxide ions (OH-) through the electrolyte from the cathode to the anode with hydrogen being generated on the cathode side. Operating at 100°–150°C, Electrolysers use a liquid alkaline solution of sodium or potassium hydroxide (KOH) as the electrolyte. In this process the anode and cathode are separated using a diaphragm that prevents remixing. At the cathode, water is split to form H2 and releases hydroxide anions that pass through the diaphragm to recombine at the anode where oxygen is produced. As this is a well-established technology it is relatively low in cost of production as well as it provides a long-time stability. However, it does have a crossover in gases possibly compromising its degree of purity and requires the use of a corrosive liquid electrolyte.

Polymer Electrolyte Membrane Electrolysers (PEM)

Polymer Electrolyte Membrane is the latest technology to be commercially used to produce hydrogen. In a PEM electrolyser, the electrolyte is a solid specialty plastic material. PEM electrolysers operate at 70°–90°C. In this the process the water reacts at the anode to form oxygen and positively charged hydrogen ions (protons). The electrons flow through an external circuit and the hydrogen ions selectively move across the PEM to the cathode. At the cathode, the hydrogen ions combine with electrons from the external circuit to form hydrogen gas. Compared to AEL there are several advantages: the product gas purity is high in a partial load operation, the system design is compact and has a rapid system response. However, component cost is high and durability is low.

Solid Oxide Electrolysers (SOE)

AEL and PEM electrolysers are known as Low-Temperature Electrolysers (LTE). However, Solid oxide Electrolyser (SOE) is known as High-Temperature Electrolyser (HTE). This technology is still at development stage. In SOE, solid ceramic material is used as the electrolyte which conducts negatively charged oxygen ions (O2-) at elevated temperatures, generates hydrogen in a slightly different way. At a temperature about 700°–800°C steam at the cathode combines with electrons from the external circuit to form hydrogen gas and negatively charged oxygen ions. The oxygen ions pass through the solid ceramic membrane and react at the anode to form oxygen gas and generate electrons for the external circuit. Advantages of this technology is that it combines high heat and power efficiency as well as it producing low emissions at a relatively low cost. Although, due to the high heat and power required, start-up time takes longer.

Why is Hydrogen being considered as an alternative fuel?

Hydrogen is considered an alternative fuel under the Energy Policy Act of 1992. Hydrogen produced via electrolysis can contribute zero greenhouse gas emissions, depending on the source of the electricity used. This technology is being pursued to work with renewable (wind, solar, hydro, geothermal) and nuclear energy options to allow virtually zero greenhouse gas and other pollutant emissions. Although, this type of production will require the cost to be decreased significantly to be competitive with more mature carbon-based pathways such as natural gas reforming. There is potential for synergy with renewable energy power generation. Hydrogen fuel and electric power generation could be distributed and sited at wind farms, thereby allowing flexibility to shift production to best match resource availability with system operational needs and market factors.

How Long will my Gas Sensor Last?

Gas detectors are used extensively within many industries (such as water treatment, refinery, petrochemical, steel and construction to name a few) to protect personnel and equipment from dangerous gases and their effects. Users of portable and fixed devices will be familiar with the potentially significant costs of keeping their instruments operating safely over their operational life. Gas sensors are understood to provide a measurement of the concentration of some analyte of interest, such as CO (carbon monoxide), CO2 (carbon dioxide), or NOx (nitrogen oxide). There are two most used gas sensors within industrial applications: electrochemical for toxic gases and oxygen measurement, and pellistors (or catalytic beads) for flammable gases. In recent years, the introduction of both Oxygen and MPS (Molecular Property Spectrometer) sensors have allowed for improved safety.  

How do I know when my sensor has failed? 

There have been several patents and techniques applied to gas detectors over the past few decades which claim to be able to determine when an electrochemical sensor has failed. Most of these however, only infer that the sensor is operating through some form of electrode stimulation and might provide a false sense of security. The only sure method of demonstrating that a sensor is working is to apply test gas and measure the response: a bump test or full calibration. 

Electrochemical Sensor  

Electrochemical sensors are the most used in diffusion mode in which gas in the ambient environment enters through a hole in the face of the cell. Some instruments use a pump to supply air or gas samples to the sensor. A PTFE membrane is fitted over the hole to prevent water or oils from entering the cell. Sensor ranges and sensitivities can be varied in design by using different size holes. Larger holes provide higher sensitivity and resolution, whereas smaller holes reduce sensitivity and resolution but increase the range. 

Factors affecting Electrochemical Sensor Life 

There are three main factors that affect the sensor life including temperature, exposure to extremely high gas concentrations and humidity. Other factors include sensor electrodes and extreme vibration and mechanical shocks.  

Temperature extremes can affect sensor life. The manufacturer will state an operating temperature range for the instrument: typically -30˚C to +50˚C. High quality sensors will, however, be able to withstand temporary excursions beyond these limits. Short (1-2 hours) exposure to 60-65˚C for H2S or CO sensors (for example) is acceptable, but repeated incidents will result in evaporation of the electrolyte and shifts in the baseline (zero) reading and slower response. 

Exposure to extremely high gas concentrations can also compromise sensor performance. Electrochemical sensors are typically tested by exposure to as much as ten-times their design limit. Sensors constructed using high quality catalyst material should be able to withstand such exposures without changes to chemistry or long-term performance loss. Sensors with lower catalyst loading may suffer damage.  

The most considerable influence on sensor life is humidity. The ideal environmental condition for electrochemical sensors is 20˚Celsius and 60% RH (relative humidity). When the ambient humidity increases beyond 60%RH water will be absorbed into the electrolyte causing dilution. In extreme cases the liquid content can increase by 2-3 times, potentially resulting in leakage from the sensor body, and then through the pins. Below 60%RH water in the electrolyte will begin to de-hydrate. The response time may be significantly extended as the electrolyte or dehydrated. Sensor electrodes can in unusual conditions be poisoned by interfering gases that adsorb onto the catalyst or react with it creating by-products which inhibit the catalyst.  

Extreme vibration and mechanical shocks can also harm sensors by fracturing the welds that bond the platinum electrodes, connecting strips (or wires in some sensors) and pins together.  

‘Normal’ Life Expectancy of Electrochemical Sensor 

Electrochemical sensors for common gases such as carbon monoxide or hydrogen sulphide have an operational life typically stated at 2-3 years. More exotic gas sensor such as hydrogen fluoride may have a life of only 12-18 months. In ideal conditions (stable temperature and humidity in the region of 20˚C and 60%RH) with no incidence of contaminants, electrochemical sensors have been known to operate more than 4000 days (11 years). Periodic exposure to the target gas does not limit the life of these tiny fuel cells: high quality sensors have a large amount of catalyst material and robust conductors which do not become depleted by the reaction. 

Pellistor Sensor 

Pellistor sensors consist of two matched wire coils, each embedded in a ceramic bead. Current is passed through the coils, heating the beads to approximately 500˚C. Flammable gas burns on the bead and the additional heat generated produces an increase in coil resistance which is measured by the instrument to indicate gas concentration. 

Factors affecting Pellistor Sensor Life 

The two main factors that affect the sensor life include exposure to high gas concentration and poising or inhibition of the sensor. Extreme mechanical shock or vibration can also affect the sensor life. The capacity of the catalyst surface to oxidise the gas reduces when it has been poisoned or inhibited. Sensor life more than ten years is common in applications where inhibiting or poisoning compounds are not present. Higher power pellistors have greater catalytic activity and are less vulnerable to poisoning. More porous beads also have greater catalytic activity as their surface volume in increased. Skilled initial design and sophisticated manufacturing processes ensure maximum bead porosity. Exposure to high gas concentrations (>100%LEL) may also compromise sensor performance and create an offset in the zero/base-line signal. Incomplete combustion results in carbon deposits on the bead: the carbon ‘grows’ in the pores and creates mechanical damage. The carbon may however be burned off over time to re-reveal catalytic sites. Extreme mechanical shock or vibration can in rare cases also cause a break in the pellistor coils. This issue is more prevalent on portable rather than fixed-point gas detectors as they are more likely to be dropped, and the pellistors used are lower power (to maximise battery life) and thus use more delicate thinner wire coils. 

How do I know when my sensor has failed? 

A pellistor that has been poisoned remains electrically operational but may fail to respond to gas. Hence the gas detector and control system may appear to be in a healthy state, but a flammable gas leak may not be detected. 

Oxygen Sensor 

Long Life 02 Icon

Our new lead-free, long-lasting oxygen sensor does not have compressed strands of lead the electrolyte has to penetrate, allowing a thick electrolyte to be used which means no leaks, no leak induced corrosion, and improved safety. The additional robustness of this sensor allows us to confidently offer a 5-year warranty for added piece of mind. 

Long life-oxygen sensors have an extensive lifespan of 5-years, with less downtime, lower cost of ownership, and reduced environmental impact. They accurately measure oxygen over a broad range of concentrations from 0 to 30% volume and are the next generation of O2 gas detection. 

MPS Sensor  

MPS sensor provides advanced technology that removes the need to calibrate and provides a ‘True LEL (lower explosive limit)’ for reading for fifteen flammable gases but can detect all flammable gases in a multi-species environment, resulting in lower ongoing maintenance costs and reduced interaction with the unit. This reduces risk to personnel and avoids costly downtime. The MPS sensor is also immune to sensor poisoning.  

Sensor failure due to poisoning can be a frustrating and costly experience. The technology in the MPS™ sensor is not affected by contaminates in the environment. Processes that have contaminates now have access to a solution that operates reliably with fail safe design to alert operator to offer a peace of mind for personnel and assets located in hazardous environment. It is now possible to detect multiple flammable gases, even in harsh environments, using just one sensor that does not require calibration and has an expected lifespan of at least 5 years. 

What are the Dangers of Confined Space Entry?

What is Confined Space and is it Classified?

Confined Space is a global concern. In this blog we are referencing the UK’s Health and Safety Executive’s dedicated documentation, as well as the United States OSHA ones, as these are broadly familiar to other countries own health and safety procedures. 

A Confined Space is a location that is substantially enclosed although not always entirely, and where serious injury can occur from hazardous substances or conditions within the space or nearby such as a lack of oxygen. As they are so dangerous, it has to be noted that any entry to confined spaces must be the only and final option in order to carry out work. Confined Spaces Regulations 1997. Approved Code of Practice, Regulations and guidance is for employees that work in Confined Spaces, those who employ or train such people and those who represent them. 

The Risks and Hazards:VOCs

A Confined Space that contains certain hazardous conditions may be considered a permit-required confined space under the standard. Permit-required confined spaces can be immediately dangerous to operator’s lives if they are not properly identified, evaluated, tested and controlled. Permit-required confined space can a defined as a confined space where there is a risk of one (or more) of the following: 

  • Serious injury due to fire or explosion 
  • Loss of consciousness arising from increased body temperature  
  • Loss of consciousness or asphyxiation arising from gas, fume, vapour, or lack of oxygen  
  • Drowning from an increase in the level of a liquid  
  • Asphyxiation arising from a free-flowing solid or being unable to reach a respirable environment due to being trapped by such a free-flowing solid 

These arise from the following hazards: 

  • Flammable substances and oxygen enrichment (read more) 
  • Excessive heat 
  • Toxic gas, fume or vapours 
  • Oxygen deficiency 
  • Ingress or pressure of liquids 
  • Free-flowing solid materials 
  • Other hazards (such as exposure to electricity, loud noise or loss of structural integrity of the space) vocs

Confined Space Identification

HSE classify Confined Spaces as any place, including any chamber, tank, vat, silo, pit, trench, pipe, sewer, flue, well or other similar space in which, by virtue of its enclosed nature, there arises a reasonably foreseeable specified risk, as outlined above.  

Most Confined Spaces are easy to identify although, identification is sometimes required as a Confined Space is not necessarily be an enclosed on all sides – some, such as vats, silos and ships’ hold, may have open tops or sides. Nor are exclusive to a small and/or difficult to work in space – some, like grain silos and ships’ holds, can be very large. They may not be that difficult to get in or out of – some have several entrances/exits, others have quite large openings or are apparently easy to escape from. Or a place where people do not regularly work – some Confined Spaces (such as those used for spray painting in car repair centres) are used regularly by people in the course of their work 

There may be instances where a space itself may not be defined as a Confined Space, however, while work is ongoing, and until the level of oxygen recovers (or the contaminants have dispersed by ventilating the area), it is classified as a Confined Space. Example scenarios are: welding that would consume some of the available breathable oxygen, a spray booth during paint spraying; using chemicals for cleaning purposes which can add volatile organic compounds (VOCs) or acidic gases, or an area subjected to significant rust which has reduced available oxygen to dangerous levels. 

What are the Rules and Regulations for Employers?

OSHA (Occupational Safety and Health Administration) have released a factsheet that highlights all the rules and regulations of residential workers in Confined Spaces.  

Under the new standards, the obligation of the employer will depend on what type of employer they are. The controlling contractor is the main point of contact for any information about PRCS on site.  

The Host employer: The employer who owns or manages the property where the construction work is taking place. 

Employer can’t rely solely on the emergency services for rescue. A dedicated service must be ready to act in the event of an emergency.  The arrangements for emergency rescue, required under regulation 5 of the Confined Spaces Regulations, must be suitable and sufficient. If necessary, equipment to enable resuscitation procedures to be carried out should be provided. The arrangements should be in place before any person enters or works in a confined space. 

The Controlling contractor: The employer who has overall responsibility for construction at the worksite. 

 The Entry employer or Sub Contractor: Any employer who decides that an employee it directs will enter a permit-required confined space. 

Employees have the responsibility to raise concern such as helping highlight any potential workplace risks, ensuring that health and safety controls are practical and increasing the level of commitment to working in a safe and healthy way.  

Testing/ Monitoring the Atmosphere:

Prior to entry, the atmosphere within a confined space should be tested to check the oxygen concentration and for the presence of hazardous gas, fume or vapour. Testing should be carried out where knowledge of the confined space (e.g. from information about its previous contents or chemicals used in a previous activity in the space) indicates that the atmosphere might be contaminated or to any extent unsafe to breathe, or where any doubt exists as to the condition of the atmosphere. Testing should also be carried out if the atmosphere is has been previously contaminated and was ventilated as a consequence (HSE Safe Work in Confined Spaces: Confined Spaces Regulations 1997 and Approved Codes of Practice). 

The choice of monitoring and detecting equipment will depend on the circumstances and knowledge of possible contaminants and you may need to take advice from a competent person when deciding on the type that best suits the situation – Crowcon can help with this.  

Monitoring equipment should be in good working order. Testing and calibration may be included in daily operator checks (a response check) where identified as necessary in accordance with our specification.  

Where there is a potential risk of flammable or explosive atmospheres, equipment specifically designed to measure for these will be required and certified Intrinsically Safe. All such monitoring equipment should be specifically suited for use in potentially flammable or explosive atmospheres. Flammable gas monitors must be calibrated for the different gases or vapours which the risk assessment has identified could be present and these may need alternative calibrations for different confined spaces. Get in touch if you require any help 

Testing should be carried out by people who are competent in the practice and aware of the existing standards for the relevant airborne contaminates being measured and are also instructed and trained in the risks involved in carrying out such testing in a confined space. Those carrying out the testing should also be capable of interpreting the results and taking any necessary action. Records should be kept of the results and findings ensuring that readings are taken in the following order: oxygen, flammable and then toxics. 

The atmosphere in a confined space can often be tested from the outside, without the need for entry, by drawing samples through a long probe. Where flexible sample tubing is used, ensure that it does not draw water or is not impeded by kinks, blockages, or blocked or restricted nozzles, in-line filters can help with this. 

What products are Intrinsically Safe and are suitable for Confined Space Safety?

These products are Certified to meet local Intrinsically Safe Standards.  

The Gas-Pro portable multi gas detector offers detection of up to 5 gases in a compact and rugged solution. It has an easy-to-read top mount display making it easy to use and optimal for confined space gas detection. An optional internal pump, activated with the flow plate, takes the pain out of pre-entry testing, and allows Gas-Pro to be worn either in pumped or diffusion modes. 

Gas-Pro TK offers the same gas safety benefits as the regular Gas-Pro, while offering Tank Check mode which can auto-range between %LEL and %Volume for inerting applications. 

T4 portable 4-in-1 gas detector provides effective protection against 4 common gas hazards: carbon monoxide, hydrogen sulphide, flammable gases, and oxygen depletion. The T4 multi gas detector now comes with improved detection of pentane, hexane, and other long chain hydrocarbons. 

Tetra 3 portable multi gas monitor can detect and monitor the four most common gases (carbon monoxide, methane, oxygen, and hydrogen sulphide), but also an expanded range: ammonia, ozone, sulphur dioxide, H2 filtered CO (for steel plants). 

Covid-19 is making oxygen management crucial for hospitals

The current Covid-19 pandemic is pushing healthcare to the limit – but oxygen management in hospitals has become a particular challenge for health systems worldwide. Within the healthcare environment, the safety of the healthcare providers and their patients is paramount.

When patients are hospitalised with Covid-19 they often need additional oxygen, and the logistics and sheer volume of this demand is forcing hospitals to take drastic action to manage oxygen use.

A recent BBC documentary, for which a film crew traced the impact of Covid-19 on the Royal Free Hospital in London, clearly shows how the problems of oxygen management are taxing front-line medics and NHS managers, and directly affecting patient care.

At the time of filming, 80% of patients at the Royal Free had Covid-19 and most were on supplementary oxygen at between five and thirty litres per second. As Rui Reis, operations manager for estates at the trust, explains in the film, the hospital used a month’s supply of oxygen in two days and was faced with the prospect of drops in the pressure of patients’ oxygen and in delivery levels – with potentially catastrophic results.

In more normal times, the hospital’s estates management could act to mitigate the problem. But all such actions would require a 4–6-hour shutdown of the oxygen supply.

And in a pandemic, that simply is not an option.

Striking a Balance

The Royal Free had never experienced such oxygen issues before, and soon realised that a balance had to be struck between reducing oxygen use and simultaneously maintaining patient care and the oxygen infrastructure. As a result, they took various measures, for example doctors decided to reduce target blood oxygen levels from 92–94% to 90–94%, while giving clinicians the option to increase oxygen levels in line with patient need. And operations director Rachel Anticoni ensured that every oxygen outlet was closed off where possible to avoid leaks, rather like stopping a dripping tap.

In the film, Rachel Anticoni reports their solutions had reduced oxygen use by around 3,000 litres per minute.

Gas monitoring makes the difference

The Royal Free offers a fine example of how good gas management can improve outcomes and operations. This is something that Crowcon knows about, because we already supply hospitals with our oxygen detectors – these provide early warning of  oxygen-riched environments (which can be an explosion risk) and can also be used to detect the leaks that drain oxygen capacity.

To summarise:

  • The Covid-19 pandemic means that hospitals must now use unprecedented amounts of oxygen.
  • This has caused them to struggle with capacity and mitigate against unnecessary use to ensure supplies are sustainable.
  • Crowcon oxygen detectors can help, by warning hospitals of oxygen leaks and preventing the occurrence of oxygen-rich environments.
  • In this way, gas monitoring protects health system resources and patients alike.

Find out more about Oxygen risks in healthcare environments in our infographic here.

If you want to know how we can help with monitoring oxygen use to ensure supply or prevent oxygen rich environments pose an explosion risk, our experts can help, please get in touch.