Connected safety – Fleet Health Monitoring for Multi-Site Fleets 

As you are no doubt aware, most gas detectors require periodic maintenance and testing, if their owners are to comply with gas safety regulations and keep their workforce safe. As you are also no doubt aware, some organisations have large numbers of gas detectors (often referred to as a fleet or fleets of devices) and keeping track of the maintenance requirements for each and every one of these can be a major headache. If the business operates from multiple sites, and especially if gas monitors move between those sites, this problem is greatly magnified. 

What is Fleet Health Monitoring? 

Many companies still manage their device fleets manually, using spreadsheets to track the location, status and calibration schedule of each detector. This is repetitive and often tedious work that takes staff away from more productive tasks. Manual management is also, frankly, inefficient. It may just about suffice for basic elements like tracking which device is where (although even that becomes cumbersome when very large numbers are involved). But when managers also need to know which devices are out of battery so cannot be used on the next shift, and which ones are showing signs of wear and tear (and they should know these things) then the data becomes too overwhelming for manual methods to handle. 

In these circumstances, it is all too easy for devices to go missing or for somebody to arrive on shift and find that the detector allocated to them is out of battery. The good news is that now, connected safety initiatives such as cloud software applications can remove these problems entirely and make fleet device management much more straightforward and efficient, even across multiple sites. 

How does it work and what are the requirements? 

Cloud software applications for gas detector fleets, such as Crowcon Connect, automatically transfer and process the gas data from gas detectors, and store it securely in the cloud in useful formats. This data includes not just exposure information, readings and times, but also more detailed information about the way in which devices are used (i.e., the extent of compliance with regulations) and who was using the device at each point (it is very easy to associate a specific user with a specific device in Crowcon Connect, for example, even if that device is part of a fleet or pool).  

Crowcon Connect can also be tailored to suit the specific requirements of a business or site, and authorised users can access the dashboard from any location, at any time. All you need is a connected device (including mobile devices; many people use their smartphones or tablets). Access can also be restricted by fleet or team, to maintain privacy where required. 

What are the benefits? 

Crowcon Connect has a user-friendly dashboard that displays user information, alarm and exposure data, device locations, dates when calibration/maintenance is due, user information and a host of other data, all in an easy-to-use format. It gives managers a panoramic view of the entire fleet, regardless of where each devices is located or has been used, and that information can be used to make safety, compliance and productivity gains and identify areas for improvement.  

This type of cloud software can also drive up safety standards, because now managers can see at a glance which devices are out of battery and cannot be used in the next shift, and/or which require maintenance. That maintenance and calibration can also be planned in ways that minimise downtime, because the dashboard lets users see the relevant dates in advance. 

What is more, because the data is collected automatically, the risk of human error is eliminated and Crowcon Connect can deliver trustworthy, complete documents that are ready for use in any compliance or safety audit.  

Want to find out more? Click here to read more about Crowcon’s own cloud software solution. 

 

Connected safety – More than Smart PPE 

Until quite recently, gas detection was widely considered to be ‘just another aspect of personal protection equipment (PPE)’, with gas detectors being fairly basic pieces of kit that detected gas hazards and nothing more. That attitude has been reinforced over years by the fact that gas detectors can be quite cumbersome things; they need bump testing and regular maintenance in order to work, which makes them something of a weak link in an increasingly digitalised, remotely-monitored, connected world. But is that attitude still fair? 

Well, no. Because just as just as every device and system  from washing machines and fridges to supply chains and enterprise equipment management – has joined the internet of things (IoT), so has gas detection. Now, just as your wearable fitness tracker can monitor your health status, and the impact of variables in your environment (exercise, food, temperature, sleep etc.), your gas monitor can connect to the web and feed data into software to generate insights that go far beyond, ‘have I been exposed to a gas hazard today?’ Becoming part of the IoT is transforming gas detection; and that transformation has only just begun. 

Where are we now with connected safety in gas detection? 

As things stand, gas detectors are increasingly connected to cloud-based software. This is often provided on a software-as-a-service (SaaS) basis by the device manufacturer, either on their own infrastructure or via a third party cloud provider. It may take the form of an app that is accessed through a web browser. The software interacts with each gas monitor in a fleet, recognising each one individually and logging data throughout each device’s operation.  

Of course, the primary purpose of gas detectors remains the safety and protection of personnel, but IoT connectivity offers many additional benefits. The scope of each software package may vary according to the provider, but good quality gas detection SaaS should provide: 

  • Remote monitoring of multiple aspects of the device (e.g., has the alarm sounded, and if so, why? When is the device due for calibration? Does it have any faults?)  
  • The ability to connect the device to the wearer (for example through RFID tags in ID badges) so that any failure to comply with proper use that is detected through the software can then be associated with a specific user. In the same way, consistent correct use is also registered. This makes it  much easier to tackle problems with non-compliance and to prove compliance at audit. 
  • The use of software to automatically upload data to the cloud also eliminates the risk of human error and greatly reduces the need for (often tedious and time-consuming) manual documentation. 
  • Above all, adding gas detectors to the IoT in this way generates lots of useful data and, importantly, presents that data in ways that make it genuinely useful. Some applications can also format and populate reports, invoices and other documentation, which can then be accessed from any mobile device with an internet connection, regardless of location.  

What can SaaS/IoT connectivity do for my fleet? 

The short answer is ‘lots’. Some examples are: 

  • Cloud software and monitoring can make it easier to locate workers and devices. This keeps workers safe and reduces device loss or theft. 
  • In today’s digital environment, the data generated by SaaS services is like gold dust: users can see at a glance which devices need to be calibrated or serviced, where they are and who has them. This information can be combined with schedules to plan service and maintenance in ways that reduce downtime and increase productivity. 
  • In a similar way, data insights can be used to identify hazardous areas (for example, repeated alarms may signal a leak) which can then be tackled proactively. 

Of course, gas detection is just at the beginning of its IoT journey: the future may hold anything from smaller wearable devices to on-site IoT drones and more. But even at this early stage, the benefits of using cloud software are clear. Click here to read more about Crowcon’s own solution.

Why it’s Important to Measure Nitrogen Oxide (NOx)?

In the EU and UK it is now obligatory for all new domestic heating and plumbing products (rated up to 400 kw) to comply with maximum nitrogen oxide (NOx) emission levels. This is line with a great deal of international regulation: NOx emissions are controlled by law or regulation in many countries (including the US, Canada, Australia and Singapore) and these may vary further by sector (maritime and automotive may have their own specific codes and limits, for example). 

The regulation of NOx required because this gas is a major pollutant, associated with thousands of deaths worldwide through its effects – both direct and indirect – on human health. It has been associated with asthma in children, lung inflammation and a host of other respiratory disorders, as well as cardiovascular damage. NOx is dangerous to animals, plants and ecosystems and is a major constituent of acid rain and smog. 

Despite its singular name, NOx is actually a collective term for nitrogen oxides – a family of highly reactive and poisonous gases – which are produced when fossil fuels are burned. Although NOx pollution is a global problem, large cities are particularly badly affected through vehicle exhaust fumes and heating system emissions; around a third of any large city’s NOx pollution comes from heating. In addition, nitrogen dioxide reacts in sunlight with other gases (such as volatile organic compounds) to generate ozone, which is a greenhouse gas.  

Why measure NOx?

Since NOx emissions are increasingly regulated, they must be measured to ensure compliance with relevant directives. The measurement of NOx from boilers and other domestic appliances is also carried out to check that these are running safely, and to ensure the owner/operator and those around them are not being exposed to excessive NOx. 

Measuring NOx with a flue gas analyser/combustion analyzer

As well as having to meet the demands of regulation, the HVAC sector recognises the growing importance of NOx measurement due to the worldwide focus on sustainability and green issues, and awareness of its harmful effects on health. This is reflected in a growing market for combustion analyzers that calculate NOx (e.g. the Sprint Pro 5 and the Sprint Pro 6).  

In the short to medium term, demand for NOx measurement seems likely to increase; the reduction of NOx emissions is a key component of sustainability policies worldwide and HVAC engineers and designers are prioritising the design of better, cleaner forms of heating (which will have to be benchmarked, verified and maintained).  

Over time, highly efficient, ultra-low-NOx systems are likely to dominate, and the measurement of NOx will therefore become an increasingly important parameter and a more prominent part of day-to-day work in the HVAC sector. 

Our Sprint Pro 5 and 6 models come complete with dedicated NO sensors allowing for a range of NO and NOx measurement options

What are Area Monitors and how do I use one?

Outdoor leaks from storage tanks or pipelines are a particular kind of hazard. With many outdoor areas not housing permanent, fixed detectors. If you’re relying solely on a personal monitor, by the time it alarms, there is a possibility that you may be engulfed in a hazardous gas cloud. Therefore, a temporary early warning system between you and the potential source of a gas hazard has the ability to alert you to trouble coming your way.

What are Area monitors and where would they be used? 

Temporary Area monitors are usually rugged units that can be placed, stand-alone to monitor a small area or multiple units can be linked together via wired or wireless networking to create a perimeter defence of a larger area. Area Monitor devices help safety personnel protect their workers from gas hazards in situations, in addition to—or sometimes in substitution of—personal, portable gas monitors used as Personal Protective Equipment (PPE). Area monitors can be positioned to produce a guard between potential hazards and workers, to notify what they are heading into or what potential hazards are coming their way.  This occurs most often when work takes place outside of normal operations where the risks are higher and/or different such as special projects, construction, maintenance, shutdowns, temporary sites or rigs, etc. In this way, they can be used to form a barrier around a tank or along a portion of pipeline close to the location of work being carried out. Portable units can be easily deployed to provide fence line monitoring during maintenance, shutdowns or turnaround. The objective is to ensure that the devices are not so far apart that gas could pass between them undetected.  If a fixed system is being taken offline for maintenance a network of fast to deploy temporary area monitors is an ideal option to use in place of the fixed system until maintenance is complete and the system is brought back online. 

How do you use one? 

Units can be connected by cables. However wireless connection between individual area monitors is also available and avoids introducing a potential trip hazard. This could add significantly to an already risky task, for example, if working at height. Some wireless systems create a “self-healing” mesh network. In this case, should the wireless connection between two devices weaken, the network will automatically re-route communications via alternate enabled devices, creating a mesh type network allowing a more robust and efficient wireless network. 

The benefit from a wireless connection is that it is practical to use repeaters or extra units to relay alerts directly to the control room. Besides the gas alert signals, some detectors will transmit other faults i.e., the loss of signal, or “battery low” alarm. This programmed alert mode is often conveyed by a specific sequence of signals, such as the beacon and lights will flash for 3 seconds followed by 5 second pause which will be repeated until an operator acknowledges the alarm. 

Wireless temporary area monitoring allows for quick deployment whilst ensuring a high level of protection for workers in circumstances where the risks are tricky to monitor. Personnel working at height can be alerted to any gas hazards on the ground, or vice versa and the same alarm can be relayed to the control room by having an additional detector in the control room. The audible alarm is significantly louder than a standard portable and light sequence is brighter and flashes faster on the Detective+ unit when gas is detected. , whilst the sequence on other units in the network is slower. This differentiates the unit nearest the gas from the rest, so everyone is alerted to the location of the hazard. In contrary, to the benefits of this products, the configuration tends to be straightforward without additional hardware. The batteries in Detective+ are larger and last longer than conventional portables. All in all, these units offer a simple yet effective solution for protecting workers outside of normal operations. 

Crowcon’s Detective+ is ideal for temporary area monitoring while workers carry out a repair. Detective+ is portable and can be easily deployed to provide fence line monitoring during shutdowns or turnaround. If working on a cooling tower fin fan, Detective+ units are connected to other units (up to 70m away) via Detective Wireless modules, which eliminate the need for cabling between units. Detective Wireless uses the proven RICOCHET mesh network. In the unusual circumstance that the wireless connection between two devices weaken, the network will automatically re-route communications via alternate RICOCHET enabled devices and so ‘self-heal’. In essence, this creates a mesh type network allowing a more robust and efficient wireless network.

Read more about Area Monitoring  

Why Do I Need a Personal Carbon Monoxide Monitor?

What is Carbon Monoxide?

Carbon monoxide (CO) is a colourless, odourless, tasteless, poisonous gas produced by incomplete burning of carbon-based fuels, including gas, oil, wood, and coal. It is only when fuel does not burn fully that excess CO is produced, which is poisonous. When the excess CO enters the body, it stops the blood from bringing oxygen to cells, tissues, and organs. CO is poisonous as you cannot see it, taste it or smell it but CO can kill quickly without warning. The Health and Safety Executive (HSE) statistics show every year around 15 people die from CO poisoning caused by gas appliances and flues that have not been correctly installed, maintained or those that are poorly ventilated. Although some levels that present do not kill but can cause serious harm to health if breathed in over a prolonged period. with extreme cases causing paralysis and brain damage because of prolonged exposure to CO. Therefore, understanding the danger of CO poisoning as well as educating the public to take appropriate precautions could inevitably reduce this risk.  

Where is CO present and why is it dangerous?

CO is present in several different industries, such as manufacturing, electricity supply, coal and metal mining, food manufacturing, oil and gas, production of chemicals and petroleum refining to name a few.  

The effects of CO poisoning, can include breathlessness, chest pain, seizures and loss of consciousness which may lead to death as well as physical problems that can occur, depending on how much CO is in the air. For example: 

CO volume (parts per million (ppm)  Physical Effects 
200 ppm  Headache in 2–3 hours 
400 ppm  Headache and nausea in 1–2 hours, life threatening within 3 hours. 
800 ppm  Can cause seizures, severe headaches and vomiting in under an hour, unconsciousness within 2 hours. 
1,500 ppm  Can cause dizziness, nausea, and unconsciousness in under 20 minutes; death within 1 hour 
6,400 ppm  Can cause unconsciousness after two to three breaths: death within 15 minutes 

 Around 10 to 15% of people who obtain serve CO poisoning go on to develop long-term complications. These include brain damage, vision and hearing loss, Parkinson’s disease, and coronary heart disease.  

How does a CO Monitor help with safety and compliance and if so, what products are available?

Any operators who are working on commercial installations or domestic application in a home are required to be registered with a relevant association, i.e., Gas safe register, Heating equipment testing and approval scheme (HETAS) – solid fuel applications and Oil firing technical association (OFTEC) – oil appliances. Therefore, personal CO monitors offer the highest quality and portability CO gas detection to protect the operator at work. 

Crowcon Clip SGD is designed for use in hazardous areas whilst offering reliable and durable fixed life span monitoring in a compact, lightweight and maintenance free device. Clip SGD has a 2-year life and is available for hydrogen sulphide (H2S), carbon monoxide (CO) or oxygen (O2). The Clip SDG personal gas detector is designed to withstand the harshest industrial working conditions and delivers industry leading alarm time, changeable alarm levels and event logging as well as user-friendly bump test and calibration solutions. 

Crowcon Gasman with specialist CO sensor is a rugged, compact single gas detector, designed for use in the toughest environments. Its compact and lightweight design makes it the ideal choice for industrial gas detection. Weighing just 130g, it is extremely durable, with high impact resistance and dust/water ingress protection, loud 95 dB alarms, a vivid red/ blue visual warning, single-button control and an easy-to-read, backlit LCD display to ensure clear viewing of gas level readings, alarm conditions and battery life. Data and event logging are available as standard, and there is a built-in 30-day advance warning when calibration is due. 

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.

 

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.

Helping you stay safe during the BBQ season

Who doesn’t love a summer BBQ? Come rain or shine we light up our BBQs with usually the only worries being whether it will rain, or the sausages are fully cooked through.

While these are important, (especially making sure the sausages are cooked!) many of us are completely unaware of the potential risks.

Carbon monoxide is a gas that has received its fair share of publicity with many of us installing detectors in our homes and businesses, but completely unaware carbon monoxide is associated with our BBQs.

If the weather is poor, we may decide to barbeque in the garage doorway or under a tent or canopy. Some of us may even bring our BBQs into the tent after use.  These can all be potentially fatal as the carbon monoxide collects in these confined areas.

Equally with a propane or butane gas canister, we store in our garages, sheds and even our homes unaware that there is a risk of a potentially deadly combination of an enclosed space, a gas leak and a spark from an electrical device.  All of which could cause an explosion.

All of that said, BBQs are here to stay and if we use them safely, are a great way to spend a summer afternoon.  So, here is a selection of facts and tips from our safety team at Crowcon which we hope will help you enjoy a safe and delicious summer ahead!

 

Quick facts and tips about BBQ charcoals:

  • Carbon monoxide is a colourless and odourless gas so just because we can’t smell or see it, doesn’t mean it’s not there
  • Carbon monoxide is a by-product of burning fossil fuels, which include charcoal and BBQ gas
  • Always use your BBQ in a well-ventilated open area as it can accumulate to toxic levels in enclosed spaces
  • Never bring a charcoal into a tent, even if it seems cold. Remember a smouldering BBQ will still give off carbon monoxide
  • Be aware and act quickly if someone experiences the symptoms of carbon monoxide poisoning which include headaches, dizziness, breathlessness, nausea, confusion, collapse and unconsciousness. These symptoms can be potentially fatal

 

Quick facts and tips about gas cannisters:

  • Gas barbecues tend to use propane, butane or LPG (which is a mixture of the two)
  • Gas BBQs have holes in the bottom to prevent a build-up of gas. This is because gas is heavier than air so will accumulate in low areas or fill a space from the bottom up
  • To avoid the accumulation of gas, cannisters should always be stored outside, upright, in a well-ventilated area, away from heat sources, and away from enclosed low spaces
  • If you store your BBQ in the garage, make sure you disconnect the gas cannister and keep this outside
  • When you are using your BBQ, keep the cannister to one side so it isn’t underneath and close to the heat source and position the BBQ in an open space
  • Always keep the cannister away from ignition sources when changing cannisters
  • Always make sure you turn off the gas at the BBQ as well as on the regulator on the cannister, after use

 

Chernobyl – a powerful safety message to the world

The recent Sky Atlantic TV series Chernobyl sent out a powerful message about the catastrophic and far reaching consequences of radiation gases, both to people and the environment.

The series is based on true events from the 1986 nuclear disaster in the then USSR; the largest uncontrolled radioactive release into the environment ever recorded. The accident resulted in an untold number of fatalities, as well as serious social and economic disruption for large populations within the USSR and beyond.

The Chernobyl explosion resulted in a radioactive gas cloud which travelled across Europe, including the UK; falling to the ground in the form of ‘nuclear rain’.

There are many disturbing facts we read about. Not least that according to the British Ministry of Health, 369 farms and 190,000 sheep in Britain still contain traces of radioactive fallout from the Chernobyl disaster.

Both human and mechanical error contributed to the disaster and thankfully safety standards, regulations, awareness and new technologies have significantly improved since the disaster.

The principal of safety, whether a huge nuclear facility or small manufacturing plant, must remain the same. Here at Crowcon we are dedicated to keeping people and the environment protected. Our technologies support organisations across multiple industries, including nuclear plants, improving plant and personal safety. Our technologies help our customers be protected from the dangers of gases.

At Crowcon, we welcome shows such as Chernobyl which document historical disasters such as this and highlight in a dramatic but real way, the importance of ensuring companies understand the need for safety measures, however big or small, are in place.  Protecting their people, the environment and the world.

#DetectingGasSavingLives

#SaferCleanerHealthier

Changes to Workplace Exposure Limits (WELs)

What Are Work Place Exposure Limits?

Workplace exposure limits (WELs) provide a legal maximum level for harmful substances in order to control working conditions.

Directive and National Standards

The EU Directive 2017/164 establishes new ‘indicative occupational exposure limit values’ (IOELVs) for a number of toxic substances. The UK Health & Safety Executive (HSE) has decided to change UK statutory limits to reflect the new IOELVs. This decision by the HSE has been taken to comply with Articles 2 and 7 of the Directive requiring Member States to establish the new occupational exposure limit values within national standards by August 21st 2018.

Gas Detector Alarm Thresholds

The exposure limits defined in this Directive 2017/164 are based on the risks of personal exposure: a workers’ exposure to toxic substances over time. The limits (configured into gas detectors as ‘TWA alarm levels’) are expressed over two time periods:

  • STEL (short-term exposure limit): a 15 minute limit
  • LTEL (long-term exposure limit): an 8-hour limit

Portable (personal) monitors are intended to be worn by the user near to their breathing zone so that the instrument can measure their exposure to gas. The instruments TWA (time-weighted) alarms will therefore alert the user when their exposure exceeds the limits set within the national standards.

Portable monitors can also be configured with ‘instantaneous’ alarms which activate immediately when the gas concentration exceeds the threshold. There are no standards to define alarm levels for instantaneous alarms, and so we have these generally set at the same thresholds as the TWA alarms. Some of the new TWA thresholds are low enough to make frequent false alarms a significant problem if they were also adopted for the instantaneous alarm setting. Therefore, new portable instruments will retain the current instantaneous alarm thresholds.

Fixed gas detectors only utilise ‘instantaneous’ alarms as they are not worn by the user and therefore cannot measure an individuals’ exposure to gas over time. Alarm levels for fixed detectors are often based on the TWA alarms as these are the only published guidelines. HSE document RR973 (Review of alarm setting for toxic gas and oxygen detectors) provides guidance on setting appropriate alarm levels for fixed detectors in consideration of site conditions and risk assessment. In some applications where there may be a background of gas it may be appropriate for fixed detector alarm levels to be set higher than those listed in EH40 to prevent repeated false alarms.

Re-configuration of Gas Detector Alarm Thresholds

Users of portable gas detectors who choose to adjust their instrument alarm thresholds to align with the Directive can easily do-so using a variety of accessories available from Crowcon. For full details of calibration and configuration accessories visit the product pages at www.crowcon.com.

Other documents you may find useful:

http://www.hse.gov.uk/pubns/priced/eh40.pdf

http://www.hse.gov.uk/research/rrhtm/rr973.html