Detecting dangers in dairy: What gases should you be aware of? 

Global demand for dairy continues to increase in large part due to population growth, rising incomes and urbanisation. Millions of farmers worldwide tend approximately 270 million dairy cows to produce milk. Throughout the dairy farm industry there are a variety of gas hazards that pose a risk to those working in the dairy industry.  

What are the dangers workers face in the dairy industry?

Chemicals

Throughout the dairy farm industry, chemicals are used for variety of tasks including cleaning, applying various treatments such as vaccinations or medications, antibiotics, sterilising and spraying. If these chemicals and hazardous substances are not used or stored correctly, this can result in serious harm to the worker or the surrounding environment. Not only can these chemicals cause illness, but there is also a risk of death if a person is exposed. Some chemicals can be flammable and explosive whilst others are corrosive and poisonous. 

There are several ways to manage these chemical hazards, although the main concern should be in implementing a process and procedure. This procedure should ensure all staff are trained in the safe use of chemicals with records being maintained. As part of the chemical procedure, this should include a chemical manifest for tracking purposes. This type of inventory management allows for all personal to have access to Safety Data Sheets (SDS) as well as usage and location records. Alongside this manifest, there should be consideration for the review of current operation.  

  • What is the current procedure?  
  • What PPE is required?  
  • What is the process for discarding out of date chemicals and is there is a substitute chemical that could pose less of a risk to your workers? 

Confined Spaces

There are numerous circumstances that could require a worker to enter a confined space, including feed silos, milk vats, water tanks and pits in the dairy industry. The safest way to eliminate a confined space hazard, as mentioned by many industry bodies, is to employ a safe design. This will include the removal of any need to enter a confined space. Although, this may not be realistic and from time to time, cleaning routines need to take place, or a blockage may occur, however, there is a requirement to ensure there is the correct procedures to address the hazard. 

Chemical agents when used in a confined space can increase the risk of suffocation with gases pushing out oxygen. One way you can eliminate this risk is by cleaning the vat from the outside using a high-pressure hose. If a worker does need to enter the confined space, check that the correct signage is in place since entry and exit points will be restricted. You should consider isolation switches and check that your staff understand the correct emergency rescue procedure if something were to happen. 

Gas Hazards

Ammonia (NH3) is found in animal waste and slurry spreading on farming and agricultural land. It is characteristically a colourless gas with a pungent smell that arises through the decomposition of nitrogen compounds in animal waste. Not only is it harmful to human health but also harmful to livestock wellbeing, due to its ability to cause respiratory diseases in livestock, and eye irritation, blindness, lung damage, alongside nose and throat damage and even death in humans. Ventilation is a key requirement in preventing health issues, as poor ventilation heightens the damage caused by this gas.  

Carbon dioxide (CO2) is naturally produced in the atmosphere; although, levels are increased through farming and agricultural processes. CO2, is colourless, odourless, and is emitted from agricultural equipment, crop and livestock production and other farming processes. CO2 can congregate areas, such as waste tanks and silos. This results in oxygen in the air to be displaced and increasing the risk of suffocation for animals and humans.  Sealed silos, waste and grain storage spaces are specifically dangerous as CO2 can accumulate here and lead to them being unsuitable for humans without an external air supply. 

Nitrogen dioxide (NO2), is one of a group of highly reactive gases known as oxides of nitrogen or nitrogen oxides (NOx). At worst, it can cause sudden death when consumed even from short term exposure. This gas can cause suffocation and is emitted from silos following specific chemical reactions of plant material. It is recognisable by its bleach-like smell and its properties tend to create a red-brown haze. As it gathers above certain surfaces it can run into areas with livestock through silo chutes, and therefore poses a real danger to humans and animals in the surrounding area. It can also affect lung function, cause internal bleeding, and ongoing respiratory problems. 

When should gas detectors be used?

Gas detectors provide added value anywhere on dairy farms and around slurry silos, but above all: 

  • When and where slurry is being mixed 
  • During pumping and bringing out slurry
  • On and around the tractor during slurry mixing or spreading 
  • In the stable during maintenance work on slurry pumps, slurry scrapers and the like 
  • Near and around small openings and cracks in the floor, e.g., around milking robots 
  • Low to the ground in poorly ventilated corners and spaces (H2S is heavier than air and sinks to the floor) 
  • In slurry silos 
  • In slurry tanks 

Products that can help to protect yourself 

Gas detection can be provided in both fixed and portable forms. Installation of a fixed gas detector can benefit a larger space to provide continuous area and staff protection 24 hours a day. However, a portable detector can be more suited for worker’s safety. 

To find out more on the dangers in agriculture and farming, visit our industry page for more information. 

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.

Where do Flue Gas Analysers Fit into the UK Government’s Decarbonisation Plans?

When the UK government announced, in March 2021, that £1 billion of already-allocated funds would be redirected to projects designed to reduce greenhouse gases, the energy sector sat up and listened. And with good reason – as it turned out, £171 million will be allocated to an industrial decarbonisation plan that focuses on hydrogen gas generation and carbon capture and storage technologies.  

However, the news extended beyond green energy production and is relevant to domestic and industrial HVAC applications. In a gesture that reflects the role HVAC engineers and manufacturers can play in sustainability, more than £900 million will be spent upgrading public buildings, like schools and hospitals, with greener fittings such as heat pumps, solar panels and insulation, which will reduce carbon dioxide (CO2) emissions.

But where does this leave the individual households and business units that many HVAC staff visit daily? That is a question that several commentators have asked, and it seems that – for now at least – the main drive to reduce the environmental impact of privately-owned heating and plumbing systems will continue to come from the manufacturers, engineers and installers working in the HVAC sector. 

And that’s quite a responsibility. According to the Office for National Statistics, in 2020, there were approximately 27.8 million households in the UK; government statistics from 2019 indicate that around 15% of greenhouse gas emissions in the UK (specifically of carbon dioxide, along with methane, F gases and nitrous oxide) came from those residential settings. That’s a lot of excess CO2 to clean up. 

So, what can HVAC people do to help decarbonisation? 

If they have decent equipment, heating engineers and plumbers can help to reduce that figure by 15%. For example, they are well placed to measure CO2 and other greenhouse gases: while most flue gas analysers will measure CO2, some can also measure NO/NOx (for example, the Sprint Pro 5 and Sprint Pro 6) well.  

A flue gas analyser that gives a wide range of easy-to-read and interprets measurements allows engineers to see when appliances are not working correctly and whether an upgrade (for example, to a government-subsidised heat pump) might be in order. 

This is a pressing need: many households hang onto appliances for as long as possible, even though older appliances tend to be much less environmentally friendly than their modern counterparts. This is bad enough for the environment, but using a malfunctioning older appliance is the worst of all possible outcomes. 

A good flue gas analyser will provide the readings required to convince many customers to decarbonise their homes or businesses more effectively. It will also allow the engineer to fix many problems in more modern and efficient appliances, bringing them back to their original operating standards and protecting the planet once more. 

Helping to reach net zero 

In late 2021, the UK government set out its plan to reach net-zero emissions by 2050 and every heating engineer in the country has a part to play in that project. While checking flue gases may be an everyday event for many HVAC engineers, the fact remains that household and business emissions account for a substantial proportion of CO2 output and emissions of other dangerous gases. While persuading a single household to operate with lower carbon emissions may not seem like a big deal, the impact can be very substantial when this is scaled up across the country. 

Green Hydrogen – An Overview

What is Hydrogen?

Hydrogen is one of the most abundant sources of gas contributing approximately 75% of the gas in our solar system. Hydrogen is found in various things including light, water, air, plants, and animals, however, it is often combined with other elements. The most familiar combination is with oxygen to make water. Hydrogen gas is a colourless, odourless, and tasteless gas which is lighter than air. As it is far lighter than air this means it rises in our atmosphere, meaning it is not naturally found at ground level, but instead must be created. This is done by separating it from other elements and collecting the gas. 

What is Green Hydrogen?

Green hydrogen is produced using electricity to power an electrolyser that separates hydrogen from the water molecule producing oxygen as a by-product. Excess electricity can be used by electrolysis to create hydrogen gas that can be stored for the future. Essentially, if the electricity used to power the electrolysers originates from renewable sources such as wind, solar or hydro, or if it originates from nuclear power – fission or fusion, then the hydrogen produced is green, in which the only carbon emissions are from those embodied in the generation infrastructure. Electrolysers are the most significant technology used for synthesising zero-carbon hydrogen fuel using renewable energy, known as green hydrogen. Green hydrogen and derivatives are an essential solution to the decarbonisation of heavy industry sectors and experts suggest will constitute up to 25% of total final energy use in a net-zero economy. 

Advantages of Green Hydrogen

It is 100% sustainable as it does not emit polluting gases either through combustion or production. Hydrogen can be easily stored thereby allowing it to be used later for other purposes and/or at the time of production. Green hydrogen can be converted into electricity or synthetic gas and can be used for a variety of domestic, commercial, industrial or mobility purposes. Additionally, hydrogen can be mixed with natural gas at ratio of up to 20% without modification of the gas main infrastructure or gas appliances.  

Disadvantages of Green Hydrogen

Although hydrogen is 100% sustainable it currently comes at a high cost than fossil fuels due to renewable energy being more expensive to produce. The overall production of hydrogen requires more energy than some other fuels, so unless the electricity required to produce hydrogen comes from a renewable source the entire process of production may be counterproductive. Additionally, hydrogen is a highly flammable gas, therefore extensive safety measures are essential to prevent leakage and explosions. 

What is The Green Hydrogen Catapult (GHC) and what does it aim to achieve? 

Members of the Green Hydrogen Catapult (GHC) are a coalition of leaders with an ambition to expand and grow Green Hydrogen Development. As of November 2021, they have announced a commitment for 45 GW of electrolysers to be developed with secured financing by 2026 with additional targeted commissioning for 2027. This is a vastly increased ambition as the initial target set by the coalition at the time of its launch in December 2020 was 25 GW. Green hydrogen has been seen as a critical element in creating a sustainable energy future as well as being one of the largest business opportunities in recent times. And has been said to be the key to allowing for the decarbonisation of sectors like steel manufacturing, shipping, and aviation.  

Why Hydrogen is seen as a cleaner future?

We live in a world in which one of the collective sustainability aims is to decarbonise the fuel we use by 2050. To achieve this, decarbonising the production of a significant fuel source like hydrogen, giving rise to green hydrogen, is one of the key strategies as production of non-green hydrogen is currently responsible for more than 2 % of total global CO2 emissions. During combustion, chemical bonds are broken and constituent elements combined with oxygen. Traditionally, Methane gas has been the natural gas of choice with 85% of homes and 40% of the UK’s electricity depending on natural gas. Methane is a cleaner fuel than coal, however, when it is burnt carbon dioxide is produced as a waste product which, on entering the atmosphere, starts contributing to climate change. Hydrogen Gas when burnt only produces water vapour as a waste product, which has no global warming potential. 

The UK Government have seen the use of hydrogen as a fuel and hence hydrogen homes as a way forward for a greener way of living, and have set a target for a thriving hydrogen economy by 2030. Whilst Japan, South Korea and China are on course to make considerable progress in hydrogen economy development with targets set to surpass the UK by 2030. Similarly, the European Commission has presented a hydrogen strategy in which hydrogen could support 24% of Europe’s energy by 2050. 

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. 

The don’ts and don’ts of zeroing your CO2 detector

Unlike other toxic gases, carbon dioxide (CO2) is all around us, albeit at levels too low to cause health issues under normal circumstances. It raises the question, how do you zero a CO2 gas detector in an atmosphere where CO2 is present?

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Carbon Dioxide – Friend and Foe?

Carbon dioxide (CO2) gas is commonly used in the manufacture of popular beverages. The leak at the Greene King brewery in Bury St Edmunds (UK) last week, is a reminder of the importance of effective gas detection. It resulted in twenty workers having to be rescued by emergency services and local residents being evacuated. So what is carbon dioxide, why is it dangerous and why do we have to monitor it carefully?

Continue reading “Carbon Dioxide – Friend and Foe?”