InHand Electronics designs and manufactures portable and handheld electronic devices that must have inherently low-power operation and high computational performance. One application area for which InHand designs and delivers electronic devices is intrinsic safety. Intrinsically safe (IS) product is designed to operate in hazardous areas, such as explosive environments, by limiting the energy available for ignition. An intrinsically safe product simplifies deployment and reduces installation costs for devices used in explosive atmospheres as compared with other protection methods. Since intrinsically safe devices are certified to be used in areas with dangerous concentrations of flammable gases or dust (such as petrochemical refineries and mines), they must pass stringent qualification and design guidelines.
In a previous blog, InHand described some of the technical challenges of device design and implementation for intrinsic safety. However design specifics is only one of the hurdles that must be cleared before getting such a device to market. This blog series addresses some of these regulations, challenges, and solutions for getting through this process.
It is important to monitor and measure a variety of parameters in explosive atmospheres, to ensure workers safety or imminent danger of explosion or other hazards. For example, a high concentration of harmful vapors could injure or sicken a worker on an oil rig. Or an increase in density of an ignition source can cause an explosion. Most electronic devices cannot be used, without modification, in environments designated as having an explosive atmosphere. This restriction is because most products, unless specifically designed to meet the stringent design criteria (including specific control and limitation of energy and heat) necessary for explosive environments, cannot pass IS certification. Without such specially designed and certified equipment, operators and companies that work in these environments may forgo acquiring some highly desired measurements.
As a device manufacturer, one of the first things to understand is that there is a not a single path to compliance – but there is typically a “best” path. Intrinsically safe design has analogies in FDA-certification (where non-compliance can be life-threatening) or space-certification (where failure can be extraordinarily costly, both in dollars and human life). A single failure could have significant ripple effects, possible causing irreparable damage to life and property. The design-guidelines and acceptable manufacturing qualifications are clear; they just need to be followed – no exceptions. There is little flexibility or tolerance with achieving compliance; either the product design meets all requirements, or it does not comply.
On first-blush, the initial set of guidelines to follow may be intimidating to the new entrants into this application area. Similar to electromagnetic compliance regulations such as FCC and CE, there are multiple worldwide standards for intrinsic safety compliance. The US, Canada, the European Union, and other non-EU countries all have their own regulations for intrinsically safe product. This seems bewildering, and arguably disastrous. However, these standards are largely harmonized. If the device manufacturer pays close attention to the level of protection and regulatory requirements needed up-front, the cross-over to worldwide use of the resulting electronic device can be a manageable project on the path to certification.
Part 2 of this blog series describes the definition of explosive atmospheres across the various worldwide standards.