Gas Detection Single Gas Detectors Introduction Portable single gas detectors are used for personal protection and have the ability to detect a single gas hazard. Typically they are small, lightweight and robust. These devices are generally worn directly on the worker s clothing or attached to Personal Protective Equipment (PPE), close to the worker s breathing area. Single gas detectors continuously monitor ambient air. When the gas concentration exceeds a limit pre-set alarm event on the device, it will alarm (by visual, audible and/or motion). This allows workers to react directly to risks. Single Portable Gas Detectors Are Available in Two Types - Disposable - Serviceable
Attributes: There are many product attributes to consider when purchasing a single gas detector. Some will be more relevant than others, it all depends on your personal preference or what your application demands. We ve explained the main attributes which should help you to find the most appropriate single gas detector. Gases - You will need to determine which gas you need to monitor. Sometimes this information is available on Material Safety Data Sheets (MSDS) or pre-testing may be carried out to understand what s in the environment. Gases include: Ammonia, Butane, Carbon Dioxide, Carbon Monoxide, Chlorine, Chlorine Dioxide, Combustible Gases, Ethanol, Ethylene Oxide, Hydrogen, Hydrogen Sulphide, Hydrogen Cyanide, Methane, Methanol, Nitric Oxide, Nitrogen Dioxide, Oxygen, Ozone, Pentane, Phosphine, Propane, Sulphur Dioxide and general Volatile Organic Compounds (VOC S). Detection Range and Resolution - Once you know which gas you need to monitor, you will need to know which gas range to use. For single portable gas detectors, this is only likely to be measured in Parts Per Million (ppm) or percentage volume (%). Advanced Features - Modern gas detectors have introduced new advanced features which can help improve product operational lifetime or safety. Wireless communication capabilities offer greater insight as to what s happening in the field. Man-Down alarm features vastly improve lone worker safety and is now a popular request for those buying wireless gas detectors. Also look out for Hibernation mode - This is being introduced to extend the gas sensor lifetime. Protective Rating - IP stands for Ingress Protection. An IP number is used to specify the environmental protection of enclosures around electronic equipment. These ratings are determined by environmental tests. The IP number is composed of two numbers, the first referring to the protection against solid objects and the second against liquids. The higher the number, the better the protection. First Number 0 No protection 1 Protected against solid objects up to 50mm³ 2 Protected against solid objects up to 12mm³ 3 Protected against solid objects up to 2.5mm³ 4 Protected against solid objects up to 1mm³ 5 Protected against dust, limited ingress (no harmful deposit) 6 Totally protected against dust Second Number 0 No protection 1 Protection against vertically falling drops of water (e.g. condensation) 2 Protection against direct sprays of water up to 15 degrees from vertical 3 Protection against direct sprays of water up to 60 degrees from vertical 4 Protection against water sprayed from all directions - limited ingress permitted 5 Protected against low pressure jets of water from all directions - limited ingress permitted 6 Protected against low pressure jets of water, limited ingress permitted (e.g. ship deck) 7 Protected against the effect of immersion between 15cm and 1m water 8 Protected against long periods of immersion under pressure
Attributes Cont: Product Lifetime - Because disposable single gas detectors are maintenance-free, they could have a maximum operational lifetime of 3 years. Serviceable gas detectors will operate for longer if the battery is changed, sensors are replaced and the gas detector is serviced and maintained regularly. Overall Cost of Ownership - In many cases, gas detectors are purchased for immediate safety, operational or legislative need, but often, little thought is given to keeping them operational and within performance requirements for their life. There are 3 main costs. a) Calibration or performance testing b) Maintenance and replacement costs c) Loss of product or replacement when units are being serviced All of these are factors that need to be considered by the user. For an in-depth overview, visit our website to download the Cost of Ownership guide or contact a1-cbiss to speak with our technical advisors Data Storage - The two types of data storage is datalogging and event logging. Event logging will only show alarm events. Gas detectors that have event logging will only have capability for a certain number of events. Datalogging allows data to be recorded at given intervals over a period of time. Sometimes, datalogging intervals can be changed by the user. Battery Type - Because disposable gas detectors are maintenance free, they will be fitted with a non-replaceable battery. Serviceable gas detectors will either have a rechargeable or a changeable battery. Technology - Single gas detection units can be supplied with gas sensors to detect the most common hazardous gases, as well as a range of more exotic gases for varying applications. Single gas detectors are also available with a PID sensor in order to detect the presence of general Volatile Organic Compounds (VOC s) and with Infrared IR sensors for the measurement of CO 2 Wireless Communications - Popularity for wireless gas detection is increasing because of the recognised benefits that it brings for protecting people and assets which save lives. The most significant advantage of wireless gas detection is the ability to broadcast real-time data 24/7 to provide instant results once engaged with a dedicated wireless network. If detection alarms are activated on remote flammable or toxic gas detectors, the response team is alerted for immediate action. The Man-Down alarm feature is a popular choice as it immediately alerts colleagues working nearby and safety officers at the control room. if alarm levels have been detected or if a worker has been overcome by hazardous gas. Fast access to critical data by local and remote monitoring teams is vital. There is no waiting for the information to be downloaded from a gas detector. Safety officers have up to date information at touch of a button. Wireless gas detection equipment is now easier than ever to deploy onto a wireless network. Gas detectors can be seamlessly added or removed. The network is self configured so monitoring begins immediately allowing communication between gas detectors or controllers. Sampling Method - A pumped instrument includes an internal sampling pump and will draw in a sample automatically when switched on. A diffusion instrument does not have a pump. Gas samples are diffused naturally. The vast majority of single gas detectors are diffusion models. Pumped models are used when the detector has a PID sensor for detecting general VOC s.
Disposable Single Gas Detectors From the list of relevant attributes above, we ve highlighted the most common attributes to help you select the appropriate disposable single gas detector. Consider the following attributes to suit your needs: Gas Product Lifetime Data Storage Product Rating Advanced Features Price Choose from CO, H 2 S, O 2 or SO 2 Up to 3 years operational lifetime Event logging only Up to IP66 or IP67 rating Hibernation mode Gases - Disposable single gas detectors are generally only available for Hydrogen Sulphide (H 2 S), Carbon Monoxide (CO), Oxygen (O 2 ) or Sulphur Dioxide (SO 2 ) Product Lifetime - Disposable gas detectors are designed to be maintenance free, therefore no calibration or servicing is required. This means that the detectors will only have an operational life of 2-3 years depending on the gas in which they are being used to measure. Data Storage - Disposable single gas detectors only offer event logging. If you require datalogging rather than event logging, consider a Serviceable single gas detector. See page 3 Protective Rating - IP67 rating means that the gas detector can be submersed in up to 1m of water and is totally protected from particulates. Advanced Features - Hibernation mode allows the gas detector to be placed in a hibernation mode when not in use. This allows for the gas detector s life to be increased from 2 years up to maximum of 3 years. a1-cbiss Recommends... Product Name Scott Safety Protege ZM BW Clip Capable of Detecting H 2 S, CO, O 2 H 2 S, CO, O 2, SO 2 Lifetime 2-3 Year Life (Hibernation) 2-3 Year Life (Hibernation) Rating IP66/67 IP67 Data Storage 25 Events Stored 35 Events Stored Advanced Feature Hibernation Mode (CO, H 2 S) Hibernation Mode Price Guide (gas dependant)
Serviceable Single Gas Detectors The full list of product attributes are on pages 2 & 3, but below, we ve listed the most common attributes to help you select the most appropriate serviceable single gas detector. Consider the following attributes to suit your needs: Gas Product Lifetime Data Storage Product Rating Advanced Features Price Choose 1 gas from 15 gas options. See page 5 for gas detection ranges Rechargeable or Changeable Battery Datalogging Up to IP67 Wireless Communications and Man-Down Alarms Gases - Serviceable single gas detectors detect oxygen, toxic gases, and are available with a PID sensor in order to detect the presence of general Volatile Organic Compounds (VOC s). Infrared IR sensors for the measurement of CO 2 and in some cases combustible gases. See page 5 for gas detection ranges. Battery Type - Serviceable gas detectors will either have a rechargeable or a changeable battery. Data Storage - The main difference between choosing a disposable or serviceable gas detector is usually based on the data storage capabilites. Most serviceable gas detectors have datalogging features. Protective Rating - IP67 rating means that the gas detector can be submersed in up to 1m of water and is totally protected from particulates. Advanced Features - Modern gas detectors have wireless communication capabilities for greater insight as to what s happening in the field. Man-Down alarm features vastly improve lone worker safety and is now a popular request for those buying wireless gas detectors. a1-cbiss Recommends... Product Name BW GasAlert Extreme ISC GasBadge Pro RAE ToxiRAE Pro Capable of Detecting 13 Gas Options 11 Gas Options 15 Gas Options Specialist Gas Options ClO 2, O 3, ETO ClO 2 CO 2, PID, LEL, ETO, CH 2 O, ClO 2 Recommended for Ozone Formaldehyde or Mercaptans Rating IP66/67 IP64 IP65 Data Storage Datalogging Datalogging Datalogging Advanced Feature inet Ready Wireless, Man-Down Alarm Price Guide (gas dependant) While every effort has been made to ensure that the information contained within this guide is comprehensive and accurate, a1-cbiss Limited will not accept any liability for errors Ready to buy? Buy online at www.a1-cbiss.com to view our product range or contact +44(0)151 666 8300 for more information