3M Gas & Flame Detection is advising businesses or public services that do not comply with updated workplace / occupational exposure limits to chemical agents, could potentially face stern consequences, including prosecution. August 2018 saw the deadline pass for compliance with the revised EU Directive 2017/164/EU. However, for businesses that remain concerned, 3M Gas & Flame Detection is offering guidance to ensure the regulations are met.
Indicative occupational exposure limit values (IOELV) are health-based, non-binding values which are derived from recent scientific data and take into account the availability of reliable measurement techniques. For any chemical agent with an IOELV set at EU level, Member States are required to establish a national occupational exposure limit. In the UK, for example, EH40 Workplace exposure limits from the Health and Safety Executive (HSE) have been updated directly in line with EU Directive 2017/164/EU. In the latest revision of EH40, which was introduced in August 2018, new limits have been introduced for 31 substances.
“The updated regulations set out the latest IOELV limits. These have been established in relation to a reference period of 8 hours and are referred to as long-term exposure limit values. In addition, for certain chemical agents, shorter reference periods exist, typically 15 minutes, and these are referred to as short-term exposure limit values. In line with the ongoing desire to create safer workplaces, IOELV limits have consequently been reduced in the updated regulations. This means any business that believes it was working safely to previous limits, may now be exceeding them.”
Neil Gwinnutt, UK & Ireland Sales Manager, 3M Personal Safety Division – Portable Gas Detection
By way of example, consider carbon monoxide (CO), which is an extremely common by-product of many industrial processes such as wastewater treatment, steelmaking, forging, chemical production, and oil and gas extraction. The 8-hour exposure limit for CO has been reduced from 30ppm to 20ppm while the 15-minute exposure limit has been tightened from 200ppm to 100ppm.
Another common gas, hydrogen cyanide (HCN), which is found widely in the plastics manufacturing industry, has seen a new 8-hour exposure limit introduced at 0.9ppm while its 15-minute exposure limit has been reduced from 10ppm to 4.5ppm.
“New limits have also been introduced for nitrogen dioxide (NO2) and nitric oxide (NO), which are commonplace in the rail industry and generated by diesel locomotives,” says Mr Gwinnutt. “As a result, rail companies need to ensure that engineers working in maintenance depots or in tunnels are not exposed to levels beyond those stated.”
The long-term effects on health resulting from exposure to chemical agents are well documented. Employers contravening the new exposure limits could not only be risking the health and safety of their team, but find themselves subject to prosecution. To help avoid this situation, any concerned employer is urged to contact 3M. The Application Engineering group offers complete end-to-end consulting, from design, through to equipment specification, installation recommendations, maintenance and service.
Certified pressure relief technology
New Ex d enclosure technology for Zone 1
R. Stahl’s new explosion-protected Ex d Ex Pressure enclosure technology is a futureproof alternative to conventional enclosure encapsulation. Complete switchgear assemblies and distribution boards can be housed in a single Ex Pressure enclosure, saving significant amounts of space and weight and making maintenance a whole lot easier. Components can be quickly retrofitted, modified or removed at any time and with little difficulty. The innovative Atex- and IECEx-certified Ex Pressure switch cabinet series features a unique pressure relief system.
Special stainless steel wire mesh ensures that pressure within the enclosure can be reduced effectively, serving as a flameproof barrier that allows for a controlled flow of gas coupled with heat absorption. This reduces the internal pressure in the event of an explosion to a maximum value of less than 1 bar; sparks that might otherwise cause an explosion are safely contained inside the enclosure thanks to the special mesh structure. The Ex d-certified pressure-relief technology allows for wall thicknesses of just 2 mm; compared to conventional Ex d flameproof enclosures, thereby helps to save space requirement and up to 50% weight. Additionally, this makes transportation, handling and installation significantly easier. The Ex Pressure concept also proves to be a viable alternative and has many attributes when compared with Ex p pressurized enclosures – it is more efficient and involves far less design work.
R. Stahl’s stainless steel enclosure with Ex Pressure technology comes in a choice of four enclosure sizes, ranging from 300 x 400 x 200 mm to 1000 x 1400 x 700 mm. These IP66-rated switch cabinets are available with either a single-leaf door or a double door. The large, undivided space inside the enclosure provides easy, unobstructed access for installation, maintenance and inspection work. The volume available within the enclosure for installing equipment is identical to that of many conventional industrial switch cabinets and control boxes and allows the switchgear layout used for non-hazardous areas to be used unchanged for hazardous areas without any additional engineering work.
More energy efficient
Expanded range of slim Ex I isolators
Explosion protection expert R. Stahl is increasingly expanding its range of intrinsically safe ISpac isolators. The latest module of the slim, continuously expanded ISpac isolator range that R. Stahl has now introduced is the 9282 temperature transmitter. The signal converter converts Ex i signals of thermocouples and resistance temperature detectors into 0/4 … 20 mA standard signals. The new devices can be operated in Zone 2 and for functional safety applications according to SIL 2. The ambient temperature ranges from -40°C to 70°C, making its application versatile and suitable for field installations in harsh climatic conditions. Furthermore, the 9282 temperature transmitters have been designed to be more energy efficient leading up to 40% savings in energy consumption while emitting less heat.
The entire isolator range for 1- and 2-channel signal transmission is available in a compact design. The slim switching repeaters, transmitter supply units and binary outputs enable an especially high signal density in an installation space that is approximately 30% smaller, thus making it an exceptionally flexible and reliable solution for safe operation of field devices in hazardous environment. Additionally, the ISpac modules that are globally certified for Zone 1 and 2, including NEC Class 1 and Division 2, fulfil the functional safety criteria according to SIL 2 or SIL 3. Tested operating periods from over 10 to 15 years guarantees availability for the long term as well as a high standard of reliability. All modules can be mounted directly on the DIN rail, snapped onto the pac-Bus and combined across all models to make them future-proof. The pac-Bus obviates the need for individual wiring, supplies up to 40 modules with auxiliary power and when combined together with the 9193 series supply module, it provides a collective fault signaling solution that is useful for overall diagnostic purposes.
The Kub reverse acting rupture disc is ideal for an extensive range of demanding industrial processes with low to high operating pressures or vacuum. The Kub is suitable for gas, liquid, vapor and two phase flow applications. The Kub is also used as a secondary device for isolating and protecting safety valves.