xvi UK Focus - Gas Detection Gas Safety in Confined Spaces


A confined space is any space large enough for someone to enter and perform assigned work, which has limited means of entry or exit, and which is not designed for continuous worker occupancy. This covers just about every industry, including utilities, construction, hydrocarbon exploration and processing, petrochemicals, marine, agriculture, food processing and brewing, as well as the emergency services.


Employers must assess the risks these workplaces pose to their employees and endeavour to prevent them. In most cases, both the assessment and the safe working system will require testing of the atmosphere with gas detection equipment.


Crowcon’s (UK) Gas-Pro multi-gas detector is ideal for this purpose. Robust, reliable and simple to use with a bright, easy to read display and long battery life, it means personnel entering confined spaces can focus on the task in hand, safe in the knowledge that their gas detector is watching their back.


Confined space gas risks can be divided into three broad categories: combustible gas, toxic gas, and oxygen depletion or enrichment.


Combustible gas risks; For combustion to occur the air must contain a minimum concentration of combustible gas or vapour. This quantity is called the lower explosive limit (LEL). Different compounds have different LELs so it’s vital that detectors are capable of detecting at the correct levels.


Typically, storage vessels which have contained hydrocarbon fuels and oils present a danger. Other dangers come from fuel leaks: burst fuel containers; pipelines on and off site, gas cylinders and engine-driven plant. For workers in pits, sewers and other sub-surface locations, methane formed by decaying organic matter is an almost universal danger.


Toxic gases and vapours; Confined-space workers may be exposed to many toxic compounds, depending on the nature of the work. A risk assessment should be made of which toxic substances a worker may be exposed to in any given work situation.


When looking at toxic gases related to specific applications, the water industry for example uses many toxic compounds for cleaning and processing both waste and clean water. Hazards such as chlorine, ozone, sulphur dioxide and chlorine dioxide then pose additional risks both in storage and treatment areas. Oxygen - too high or too low?; The normal concentration of oxygen in fresh air is 20.9%. An atmosphere is hazardous if the concentration drops below 19.5% or goes above 23.5%.


Without adequate ventilation, the simple act of breathing will cause oxygen levels to fall surprisingly quickly. Combustion also uses up oxygen, so engine-driven plant and naked flames such as welding torches are potential hazards. Oxygen can also be displaced. Nitrogen, for example, when used to purge hydrocarbon storage vessels prior to re-use, drives oxygen out of the container and leaves it highly dangerous until thoroughly ventilated. High oxygen levels are also dangerous. As with too little, too much will impair the victim's ability to think clearly and act sensibly. Moreover, oxygen-enriched atmospheres represent a severe fire hazard.


Both portable and fixed gas detectors can be used for confined space monitoring. Fixed systems typically comprise one or more detector "heads" connected to a separate control panel. If a detector reads a dangerous gas level, the panel raises the alarm by triggering external sirens and beacons. This sort of installation is suited to larger spaces like plant rooms, which have sufficient room for the hardware or remote stations that are usually unmanned.


However, much confined space work takes place in more restricted areas, making compact portable units more suitable. Ease of use, with one button operation, means minimal training is required while increased safety is ensured. Combining one or more sensors with powerful audible and visual signals to warn when pre-set gas levels are reached, portable detectors can be carried or worn wherever they are needed. In addition, a compact instrument is easily carried in a confined space, ensuring that pockets of high gas concentration are not missed.


Certain features should be expected in every portable gas detector. Clearly, life-saving tools for demanding environments must be as tough as possible, with reliable electronics housed in impact-resistant casings. While the need to leave gas sensors exposed to the atmosphere means that no instrument can be fully sealed, a high degree of protection against dust and water ingress is essential. Toughness notwithstanding, a well-designed detector will also be light and compact enough to wear for an entire shift.


Finally, because of the difficulties of working in a cramped space, perhaps under poor lighting, instruments should be easy to use. No matter how advanced a detector's internal architecture or data management options, personnel in the field should be faced with nothing more daunting than a clear display, simple, one-button operation and loud/bright alarms.


For More Info, email: 24643pr@reply-direct.com


a1-cbiss Provide ‘Belt & Braces’ Approach to Plant Maintenance


Maintenance on plant and equipment is often carried out to prevent problems arising, ensure equipment is working effectively and to increase reliability. Usually these programs are continuous over the year and present the cost benefits of better productivity and efficiency. This level of high quality is usually maintained by a complete plant shutdown every 12 or 18 months.


Plant shutdowns for planned major maintenance work are the most expensive and time- consuming of maintenance projects because of the loss of production and the expense of the turnaround itself.


For plant shutdown to go as planned, extra gas detection equipment may be needed to accelerate the maintenance program. During plant shut downs, storage tanks, silos and warehouses may be cleaned or flushed out by maintenance teams. Therefore, plant managers to must guarantee worker safety upon entry to these areas. Confined space entry equipment must be available to protect maintenance teams against harmful hazardous process chemicals.


Here at a1-cbiss we will work with you during the project to ensure that everything operates in accordance and your maintenance workers have the confidence in the supplied gas detection equipment. a1-cbiss are able to supply a wide range of gas detectors to provide exceptional protection in the harshest of industrial environments.


Product training can be provided to ensure that workers understand how their equipment works and what to do in the event of an alarm.


A popular choice for plant maintenance is the BM25 from Industrial Scientific. Packing all the benefits of a fixed detector into a portable detector, the BM25 is a rugged area monitor that is often used alongside personal gas detectors to provide a tough ‘belts and braces’ safety approach.


Designed to work in hazardous areas for prolonged periods of time, the BM25 is equipped as standard with a high capacity battery pack, offering up to 170 hours uninterrupted battery run time. The BM25 is able to provide early indication of toxic and combustible gas leaks using powerful audible (103 dB) and bright, flashing visual alarms to alert personnel, giving users peace of mind.


The Ventis MX4 is a suitable multi-gas counterpart for the BM25. Usually worn on a belt or clipped to work wear, this multi-gas detector can provide detection of 1-4 gases with a continuous run time of up to 20 hours. Equipped with three separate alarms; vibrate (for noisy or brightly lit environments), visible flashing beacon (for noisy or dark environments), and an audible alarm (for dark environments). The user can select the most appropriate alarm type or equip all 3 at once.


The detectors feature a bump test and self test on start-up, which allows the factory engineers to optionally configure the instrument to perform a self test or execute a bump test procedure during instrument start-up. This provides the ability to ensure that instruments are properly tested before each use.


a1-cbiss hire any numbers of gas detection equipment and for short or long periods of time, allowing for a smooth cost-effective shutdown. You won’t have to worry about storing or maintaining the detectors fleet.


email: 357ad@reply-direct.com For More Info, email: IET September / October 2013 www.envirotech-online.com 26794pr@reply-direct.com


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68