TWA Resume – how Crowcon’s patented feature keeps workers safe and makes compliance easier

Most people who work with hazardous gases, and particularly anyone with responsibility for regulatory compliance, will be familiar with the various ways of measuring workplace exposures to gas. You may have heard of short- and long-term exposure limits; these are used to quantify the amount of gas a worker can be exposed to without harm, and most gas detectors track them.

But why differentiate between a short-term and long-term exposure? Well, that has mainly to do with the ways in which gases can be harmful. Some gases (hydrogen cyanide, for example) can be almost immediately fatal if inhaled at a given concentration, but some gases remain harmless if present at or below a much lower level for extended periods of time.

If a worker’s long-term exposure is more than the safe level, however, then some gases can be seriously dangerous to health. And the company in charge may become legally liable because it will have failed to comply with gas regulations.

Non-compliance can get very expensive, very quickly. It is costly in both financial and reputational terms.

Figure 1: This image shows how Crowcon’s proprietary TWA Resume feature keeps workers safe and proves a firm’s compliance, by continuing to monitor exposure to harmful gases even after a mid-shift break or other switch-off during the TWA period. Other detectors don’t do this, they assume any switch-off (e.g. for meals or to drive between sites) signals a new period of measurement, which leaves workers vulnerable to over-exposure and harm, and firms open to legal sanctions due to harm and/or non-compliance. In this image, you can see the workplace exposure limit is breached at around 14:00, but only the Crowcon device with TWA Resume alerts the user to this fact and documents it.

Why use TWAs?

Long-term and short-term workplace exposure limits (WELs) for gases are set out by local regulatory bodies. In the UK, the HSE document EH40 applies. Chronic exposure is often measured via a time-weighted average, or TWA. That means the worker’s exposure to a gas is monitored across a given period, usually 8 hours, to make sure the gas(es) remain(s) at or below the WEL throughout that time.

Unfortunately, it is incredibly easy to mess up a TWA measurement and thus fall foul of the regulations. This is because many standard gas detectors erase the TWA timer history when they are switched off, even if the 8-hour/TWA measurement period is ongoing. So, if an operator turns off one of these detectors because they are having lunch or moving between sites, then switches it back on again when they get back to work (bearing in mind this is a continuation of the TWA period they have already begun to track), the detector will assume that they are beginning a new TWA measurement period.

Clearly, this breaches regulations and can be very dangerous – Figure 1, above, shows why. In this example, the worker exceeds the safe limit at around 14:00 but the traditional device does not ‘see’ this or alert them. The Crowcon device with TWA Resume, however, does sound the alert. And that may save both the worker and the company from a great deal of harm.

What is TWA Resume?

The Crowcon T4 and Gas-Pro ranges have Crowon’s proprietary TWA Resume feature. This  innovative and unique functionality makes sure accurate TWAs are recorded for each and every 8-hour/TWA period, keeping employees safe and removing the risk of non-compliance. Furthermore, it makes it easy for a firm to prove their compliance in the face of any legal claim.

TWA Resume is a patented feature only found on Crowcon devices. When turned off during the TWA measurement period, it stores TWA data in its memory. When a worker switches it back on, they can choose to resume measurement from where it left off, or start a new TWA measurement.

T4 and Gas-Pro detectors store this data in their logs, where is available for further analysis and to prove compliance. Even better, TWA alarms and near-miss data can now be easily exported into Crowcon Connect, a cloud-based portal that gives customers total data visibility. This makes it easy for them to prove compliance, and to be sure that their workers are safe.

Because TWA Resume is a patented Crowcon feature, only Crowcon can provide it. If you want to keep your staff safe while making regulatory compliance much easier, please contact us. We’ll be happy to give you more information on our patented TWA resume feature and discuss how it can help you and your business.

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.

Are you safe to re-start operations?

As governments around the world ease lockdown measures that were introduced to combat Covid-19, many of us are starting to plan how to return to business. But re-starting operations after a break can present specific gas-related problems and dangers that must be dealt with before operations begin.

A terrible example of what can happen otherwise has recently occurred in India. There, a persistent styrene leak, from a factory that had been closed due to the Covid-19 outbreak, killed at least 11 people, and harmed many more within a radius of several kilometres.

The need to check gas safety after a break in operations applies across many sectors. These include:

-Car plants

-Manufacturing facilities of all types

-Bars, restaurants and hospitality venues

-Leisure centres and swimming pools

-Refineries and chemical processing plants, where operations have been scaled back or stopped due to reduced demand

-Laboratories

-Schools and colleges

-General industrial sites that ceased operations due to Covid-19.

What are the dangers?

While the challenges arising will vary by sector, the most common include:

  • Re-pressurisation of systems. Many industries – from schools and colleges to bars and oil refineries – use pressurised systems or equipment such as boilers, steam heating systems, autoclaves, pipework, heat exchangers and refrigeration plant. If these are not correctly pressurised, they may explode, leak or cause contact injuries Any break in operations may have caused or coincided with a change (usually a drop) in pressure.

Some systems contain gases that are inherently toxic/flammable, some gases may be safe in normal process conditions but are now less safe due to changes in pressure or other conditions created by a recent shut-down. In any case, there is a legal duty to maintain pressurised systems (you can find out more from the HSE’s pages here) so it makes sense to check the system before re-starting operations, and to re-pressurise the system if required.

  • Areas used to store toxic and/or flammable gases that have not been entered for some time. This is likely to be a widespread danger because such areas are not always industrial. Swimming pool operators store chlorine; cafes, schools and colleges store gases for educational and catering purposes; food-makers, pubs and bars use gases in the manufacture and dispensing of beverages. If gas has leaked during a Covid-19 shut-down, it may endanger property and staff when operations begin again. Alternatively, the break could mean that gases are no longer stored at their optimum pressure or temperature.
  • It should also be noted that some stored goods may emit toxic or flammable gases if they have been left for a long period. For example, methane and hydrogen sulphide may be generated by organic matter that has begun to degrade or ferment.
  • Re-starting production or operations where materials/chemicals have been left unattended for some time can also be hazardous. For example, anything stored at a specific pressure may have experienced a change in that pressure, and materials stored in sub-optimal conditions (e.g. in terms of ambient temperature, pressure, exposure to light or operation) may now be unfit for purpose or even dangerous.

What should I do before re-starting operations?

Gas hazards should form part of your re-starting operations risk assessment.

When it comes to gas, Crowcon has a wealth of knowledge gathered over many years and from many installations. If you need reliable information about the gas-related dangers that may arise on your own return to operations, check out our ‘Talking Gas’ information hub, which is full of free resources to download, and our ‘Insights’ knowledge base. And if you have any other questions relating to the post-Covid return, please get in touch.

 

How aware of cross-sensitivities when using gas detectors are you?

In a perfect world, gas detector sensors would identify, isolate and measure specific gases and give precise readings for each gas in any context. Unfortunately, technology allows us to come close to that but not to achieve it completely. That is why, when dealing with electrochemical toxic sensors, we have the challenge of cross-sensitivities, sometimes known as ‘interfering gasses’.

Gas detectors generally detect a specified gas and give an alarm and/or reading in proportion to the level present. Cross-sensitivity occurs when a gas other than the gas being monitored/detected can affect the reading given by an electrochemical sensor. This causes the electrode within the sensor to react even if the target gas is not actually present, or it causes an otherwise inaccurate reading and/or alarm for that gas. Obviously, this puts the person using the sensor at risk.

Inaccuracies caused by cross-sensitivity

How not to use a gas detectorCross-sensitivity may cause several types of inaccurate reading in electrochemical gas detectors. These can be positive (indicating the presence of a gas even though it isn’t actually there, or indicating a level of that gas above its true value), negative (a reduced response to the target gas, suggesting that it is absent when it is actually present, or a reading that suggests there is a lower concentration of the target gas than there is), or the interfering gas can cause inhibition.

Inhibition occurs when the sensor simply fails to register the target gas when it is exposed to the target gas and the inhibitor together, or the inhibitor causes the sensor to stop registering the target gas for some time (which may be hours or even days) after exposure to the inhibitor.

Here are some examples of each error type:

  • Positive response error: a CO sensor has a positive response to H2 at a rate of 60%. Thus, when the sensor detecting CO sees 200ppm of H2 it indicates 60% of 200ppm (around 120ppm).
  • Negative response error: an SO2 sensor has a –120% response to NO2. So, if it sees 5ppm of NO2 at the same time as 5ppm of SO2, the reading is reduced by 6ppm, which (depending on the type of sensor involved) gives a 0ppm reading or negative value.
  • Inhibition: SO2 sensors may be inhibited by NH3, and take many hours to recover and respond to SO2

All of these errors can have adverse effects. Clearly, danger arises when toxic gas is present and the sensor does not read correctly. But even when cross-sensitivity causes an over-reading or false positive, time and resources can be wasted by needless evacuations, ventilation and other unscheduled downtime.

Some manufacturers publish cross-sensitivity data and charts, and these can give some indication of how cross-sensitivities may influence readings in those products. However, it is important not to rely on these too heavily: there can be huge differences between electrochemical sensors, manufacturers may change their sensor designs and specifications at short notice, and scientific understanding is constantly evolving. So, it is a good idea to maintain dialogue with the manufacturer’s technical support team, who will be aware of the latest information and best placed to advise on a particular sensor. It is also sensible to ensure that any staff involved in gas detection are aware of the nature of cross-sensitivity and interference, and alert to its likely effects.

Keeping your gas monitors clean during COVID-19

During this challenging time, keeping your gas monitor clean is more important than ever to ensure you’re keeping yourself, and others, safe.

Cleaning your monitor

The following procedure and precautions should be noted if you intend to clean your Crowcon gas monitor to protect against COVID-19 transmission.

Gas monitors contain sensors that may be affected by the chemicals in cleaning compounds. In general Crowcon recommends cleaning with mild soap and a soft cloth taking care not to introduce excessive amounts of liquid into the product/sensors.

Alcohol-based cleaning products may cause a temporary response on some electrochemical sensors; potentially leading to false-alarms. It is recommended monitors are switched-off before cleaning and not switched back on until the alcohol has fully evaporated.

Cleaning agents that contain chlorine and/or silicones must be avoided, especially on monitors that contain pellistor-type flammable gas sensors as these compounds will ‘poison’ the sensor leading to permanent loss of sensitivity to gas.

Where gas monitor cleaning regimes are introduced or increased Crowcon strongly recommends that sensors are bump tested with the target gas periodically to ensure that sensors remain operational. Pellistor-type sensors in portable monitors should be tested every day before use as prescribed in the European standard EN60079-29 Part 1.

It is extremely likely that any viral agent could get trapped within the pump or filters within an instrument. Maintenance procedures should continue to be performed as described in the Operation and Maintenance Manual for the product and in-line with operating company policy.

For more information on how to keep you or your business safe during the COVID19 pandemic, get in touch and we’d be more than happy to help.

What is the life expectancy of my sensors?

Given the critical nature of gas detectors, it is important to know they are working correctly at all times. Many factors can affect the performance of gas detection sensors, and all sensors will fail eventually, so users must be vigilant and prepared to change their sensors when required. But changing sensors too early, when they actually have plenty of life left, can be a waste of time and money.

A further issue arises with purchasing and storing spares. Replacement sensors have a finite shelf life, which begins from the moment they are made. As time passes, they can degrade even if kept in ideal conditions (i.e. in a contaminant-free, temperature and humidity controlled environment  so the period between purchase and first use should be brief.

So, what should users do to extend the life of their sensors without putting people at risk?

Factors affecting sensor life

The life and/or performance of gas detection sensors can be affected by various factors, including:

  • Temperature
  • Humidity
  • Interfering gases
  • Physical factors, e.g. excessive vibration or impact
  • Contamination of or damage to the sensor e.g. by incorrect cleaning products
  • Contamination of filters or sinters e.g. by dust, sand or pests (yes spiders!)
  • Exposure to poisoning/inhibiting compounds even when the sensor is not powered.

There are multiple sensing technologies available and the life expectancy of a sensor is commonly linked to the technology employed. Electrochemical sensors tend to have a shorter life expectancy as compared to Infrared (IR) or catalytic sensors. The type of gas being detected can also have an impact of the life expectancy,  the more ‘exotic’ gases (for example chlorine or ozone) tends to be shorter than that of sensors monitoring the more common gases (carbon monoxide, hydrogen sulphide for example).

Most sensors will also suffer general wear and tear, and the damage caused is not always easy to detect, so the first rule for keeping sensors safe and in good working order is to undertake regular maintenance. This should include scheduled bump testing (also known as a gas or functional test) and calibration; while exposure to substantial volumes of gas may harm some sensors, the small amounts used in bump testing and calibration are absolutely fine

It is not always easy to tell that a sensor has failed; some of the techniques suggested are unreliable and this is not an area in which to take risks. The only sure-fire way to know a sensor is working correctly is through application of the target gas(es) in bump testing/calibration.

Planning gas sensor replacement

It makes sense for users to extend the life of their sensors as far as possible; they cost time and money to replace, after all. The ability to forward-plan and predict sensor consumption also makes sensor purchasing more efficient and helps to reduce the time spare sensors are kept in storage.

To predict and plan sensor replacement, users must understand the factors that influence their sensors’ performance. These will be specific to their own setting, which is why users must also be able to draw upon knowledge and experience built up through regular testing and calibration of sensors in their particular environment and applications.

Good quality sensors will come with a warranty, but while this may indicate a general life expectancy there are too many variables and too much at stake for it to stand alone. There really is no substitute for user knowledge and regular maintenance: with these in place, gas detector sensors are far more likely to live long and prosper.

What’s the difference between a pellistor and an IR sensor?

Sensors play a key role when it comes to monitoring flammable gases and vapours. Environment, response time and temperature range are just some of the things to consider when deciding which technology is best.

In this blog, we’re highlighting the differences between pellistor (catalytic) sensors and infrared (IR) sensors, why there are pros and cons to both technologies, and how to know which is best to suit different environments.

Pellistor sensor

A pellistor gas sensor is a device used to detect combustible gases or vapours that fall within the explosive range to warn of rising gas levels. The sensor is a coil of platinum wire with a catalyst inserted inside to form a small active bead which lowers the temperature at which gas ignites around it. When a combustible gas is present the temperature and resistance of the bead increases in relation to the resistance of the inert reference bead. The difference in resistance can be measured, allowing measurement of gas present. Because of the catalysts and beads, a pellistor sensor is also known as a catalytic or catalytic bead sensor.

Originally created in the 1960’s by British scientist and inventor, Alan Baker, pellistor sensors were initially designed as a solution to the long-running flame safety lamp and canary techniques. More recently, the devices are used in industrial and underground applications such as mines or tunnelling, oil refineries and oil rigs.

Pellistor sensors are relatively lower in cost due to differences in the level of technology in comparison to IR sensors, however they may be required to be replaced more frequently.

With a linear output corresponding to the gas concentration, correction factors can be used to calculate the approximate response of pellistors to other flammable gases, which can make pellistors a good choice when there are multiple flammable vapours present.

Not only this but pellistors within fixed detectors with mV bridge outputs such as the Xgard type 3 are highly suited to areas that are hard to reach as calibration adjustments can take place at the local control panel.

On the other hand, pellistors struggle in environments where there is low or little oxygen, as the combustion process by which they work, requires oxygen. For this reason, confined space instruments which contain catalytic pellistor type LEL sensors often include a sensor for measuring oxygen.

In environments where compounds contain silicon, lead, sulphur and phosphates the sensor is susceptible to poisoning (irreversible loss of sensitivity) or inhibition (reversible loss of sensitivity), which can be a hazard to people in the workplace.

If exposed to high gas concentrations, pellistor sensors can be damaged. In such situations, pellistors do not ‘fail safe’, meaning no notification is given when an instrument fault is detected. Any fault can only be identified through bump testing prior to each use to ensure that performance is not being degraded.

 

IR sensor

Infrared sensor technology is based on the principle that Infrared (IR) light of a particular wavelength will be absorbed by the target gas. Typically there are two emitters within a sensor generating beams of IR light: a measurement beam with a wavelength that will be absorbed by the target gas, and a reference beam which will not be absorbed. Each beam is of equal intensity and is deflected by a mirror inside the sensor onto a photo-receiver. The resulting difference in intensity, between the reference and measurement beam, in the presence of the target gas is used to measure the concentration of gas present.

In many cases, infrared (IR) sensor technology can have a number of advantages over pellistors or be more reliable in areas where pellistor-based sensor performance can be impaired- including low oxygen and inert environments. Just the beam of infrared interacts with the surrounding gas molecules, giving the sensor the advantage of not facing the threat of poisoning or inhibition.

IR technology provides fail-safe testing. This means that if the infrared beam was to fail, the user would be notified of this fault.

Gas-Pro TK uses a dual IR sensor – the best technology for the specialist environments where standard gas detectors just won’t work, whether tank purging or gas freeing.

An example of one of our IR based detectors is the Crowcon Gas-Pro IR, ideal for the oil and gas industry, with the availability to detect methane, pentane or propane in potentially explosive, low oxygen environments where pellistor sensors may struggle. We also use a dual range %LEL and %Volume sensor in our Gas-Pro TK, which is suitable for measuring and switching between both measurements so it’s always safely operating to the correct parameter.

However, IR sensors aren’t all perfect as they only have a linear output to target gas; the response of an IR sensor to other flammable vapours then the target gas will be non-linear.

Like pellistors are susceptible to poisoning, IR sensors are susceptible to severe mechanical and thermal shock and also strongly affected by gross pressure changes. Additionally, infrared sensors cannot be used to detect Hydrogen gas, therefore we suggest using pellistors or electromechanical sensors in this circumstance.

The prime objective for safety is to select the best detection technology to minimise hazards in the workplace. We hope that by clearly identifying the differences between these two sensors we can raise awareness on how various industrial and hazardous environments can remain safe.

For further guidance on pellistor and IR sensors, you can download our whitepaper which includes illustrations and diagrams to help determine the best technology for your application.

You won’t find Crowcon sensors sleeping on the job

MOS (metal oxide semiconductor) sensors have been seen as one of the most recent solutions for tackling detection of hydrogen sulphide (H2S) in fluctuating temperatures from up to 50°C down to the mid-twenties, as well as humid climates such as the Middle East.

However, users and gas detection professionals have realised MOS sensors are not the most reliable detection technology. This blog covers why this technology can prove difficult to maintain and what issues users can face.

One of the major drawbacks of the technology is the liability of the sensor “going to sleep” when it doesn’t encounter gas for a period of time. Of course, this is a huge safety risk for workers in the area… no-one wants to face a gas detector that ultimately doesn’t detect gas.

MOS sensors require a heater to equalise, enabling them to produce a consistent reading. However, when initially switched on, the heater takes time to warm up, causing a significant delay between turning on the sensors and it responding to hazardous gas. MOS manufacturers therefore recommend users to allow the sensor to equilibrate for 24-48 hours before calibration. Some users may find this a hinderance for production, as well as extended time for servicing and maintenance.

The heater delay isn’t the only problem. It uses a lot of power which poses an additional issue of dramatic changes of temperature in the DC power cable, causing changes in voltage as the detector head and inaccuracies in gas level reading. 

As its metal oxide semiconductor name suggests, the sensors are based around semiconductors which are recognised to drift with changes in humidity- something that is not ideal for the humid Middle Eastern climate. In other industries, semiconductors are often encased in epoxy resin to avoid this, however in a gas sensor this coating would the gas detection mechanism as the gas couldn’t reach the semiconductor. The device is also open to the acidic environment created by the local sand in the Middle East, effecting conductivity and accuracy of gas read-out.

Another significant safety implication of a MOS sensor is that with output at near-zero levels of H2S can be false alarms. Often the sensor is used with a level of “zero suppression” at the control panel. This means that the control panel may show a zero read-out for some time after levels of H2S have begun to rise. This late registering of low-level gas presence can then delay the warning of a serious gas leak, opportunity for evacuation and the extreme risk of lives.

MOS sensors excel in reacting quickly to H2S, therefore the need for a sinter counteracts this benefit. Due to H2S being a “sticky” gas, it is able to be adsorbed onto surfaces including those of sinters, in result slowing down the rate at which gas reaches the detection surface.

To tackle the drawbacks of MOS sensors, we’ve revisited and improved on the electrochemical technology with our new High Temperature (HT) H2S sensor for XgardIQ. The new developments of our sensor allow operation of up to 70°C at 0-95%rh- a significant difference against other manufacturers claiming detection of up to 60°C, especially under the harsh Middle Eastern environments.

Our new HT H2S sensor has been proven to be a reliable and resilient solution for the detection of H2S at high temperatures- a solution that doesn’t fall asleep on the job!

Click here for more information on our new High Temperature (HT) H2S sensor for XgardIQ.

An ingenious solution to the problem of high temperature H2S

Due to extreme heat in the Middle East climbing up to 50°C in the height of summer, the necessity for reliable gas detection is critical. In this blog, we’re focusing on the requirement for detection of hydrogen sulphide (H2S)- a long running challenge for the Middle East’s gas detection industry.

By combining a new trick with old technology, we’ve got the answer to reliable gas detection for environments in the harsh Middle Eastern climate. Our new High Temperature (HT) H2S sensor for XgardIQ has been revisited and improved by our team of Crowcon experts by using a combination of two ingenious adaptations to its original design.

In traditional H2S sensors, detection is based on electrochemical technology, where electrodes are used to detect changes induced in an electrolyte by the presence of the target gas. However, high temperatures combined with low humidity causes the electrolyte to dry out, impairing sensor performance so that the sensor has to be replaced regularly; meaning high replacement costs, time and efforts.

Making the new sensor so advanced from its predecessor is its ability to retain the moisture levels within the sensor, preventing evaporation even in high temperature climates. The updated sensor is based on electrolytic gel, adapted to make it more hygroscopic and avoiding dehydration for longer.

As well as this, the pore in the sensor housing has been reduced, limiting the moisture from escaping. This chart indicated weight loss which is indicative of moisture loss. When stored at 55°C or 65°C for a year just 3% of weight is lost. Another typical sensor would lose 50% of its weight in 100 days in the same conditions.

For optimal leak detection, our remarkable new sensor also features an optional remote sensor housing, while the transmitter’s displays screen and push-button controls are positioned for safe and easy access for operators up to 15metres away.

 

The results of our new HT H2S sensor for XgardIQ speak for themselves, with an operating environment of up to 70°C at 0-95%rh, as well featuring a 0-200ppm and T90 response time of less than 30 seconds. Unlike other sensors for detecting H2S, it offers a life expectancy of over 24 months, even in tough climates like the Middle East.

The answer to the Middle East’s gas detection challenges fall in the hands of our new sensor, providing its users with cost-effective and reliable performance.

Click here for more information about the Crowcon HT H2S sensor.

Have you ever thought about the dangers behind your favourite beverage?

Beer Production

It’s only natural for us to associate the need for gas detection in the oil and gas, and steel industries, but have you thought about the need to detect hazardous gases such as carbon dioxide and nitrogen in the brewing and beverage industry?

Maybe it’s because nitrogen (N2) and carbon dioxide (CO2) are naturally present in the atmosphere. It could be that CO2 is still under-valued as a hazardous gas. Although in the atmosphere CO2 remains at very low concentrations – around 400 parts per million (ppm), greater care is needed in brewery and cellar environments where in confined spaces, the risk of gas canisters or associated equipment leaking could lead to elevated levels. As little as 0.5% volume (5000ppm) of CO2 is a toxic health hazard. Nitrogen on the other hand, can displace oxygen.

CO2 is colourless, odourless and has a density which is heavier than air, meaning pockets of CO2 gather low on the ground gradually increasing in size. CO2 is generated in huge amounts during fermentation and can pose a risk in confined spaces such as vats, cellars or cylinder storage areas, this can be fatal to workers in the surrounding environment, therefore Health & Safety managers must ensure the correct equipment and detectors are in place.

Brewers often use nitrogen in multiple phases of the brewing and dispensing process to put bubbles into beer, particularly stouts, pale ales and porters, it also ensures the beer doesn’t oxidise or pollute the next batch 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.

Gas detection can be provided in the form of both fixed and portable. 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, 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 belts or clothing and will detect pockets of CO2 using alarms and visual signals, indicating that the user should immediately vacate the area.

At Crowcon, we’re dedicated in growing a safer, cleaner, healthier future for everyone, every day by providing best in class gas safety solutions. It’s vital that once gas detectors are deployed, employees should not get complacent, and should be making the necessary checks an essential part of each working day as early detection can be the difference between life and death.

Quick facts and tips about gas detection in breweries:

  • Nitrogen and CO2 are both colourless and odourless. CO2 being 5 times heavier than air, making it a silent and deadly gas.
  • Anyone entering a tank or other confined space must be equipped with a suitable gas detector.
  • Early detection can be the difference between life and death.