Twenty years ago, certified industrial hygienists (CIHs) had discreet roles with instrumentation to match. Gas monitors had optional “hygiene”-printed circuit boards for data collection of gas readings for short-term exposure limits (STELs) and time-weighted average (TWA) calculations. Obviously, anything deemed optional equated to “extra” and therefore had a higher cost.
These techie tools were near-scientific measuring devices, with real-time direct readings and off-line data graphing software programs. Corporate CIH professionals essentially would act as internal consultants, using special gas detectors with these extra features to analyze the atmospheric conditions of the workplace. To safety managers and end users, these features were “bells and whistles” that were unnecessary for everyday use.
Bells and whistles, as defined in the American Heritage Dictionary, are “nonessential features or enhancements intended especially to add commercial appeal.” The online reference Dictionary.com defines “bells and whistles” as “features added to a product; special parts or functions; extras.” There’s no question that when used in conversation, a product with “bells and whistles” is understood as something loaded with features.
IH Monitoring Is Commonplace
With the onset of regulatory requirements for monitoring atmospheric conditions in confined spaces, underground mines, etc., gas monitors are used in virtually every workplace setting. Where gas monitors were once considered specialty equipment, they now have become standard-issue gear, often for an entire work force – and are prolific to the degree of commoditization.
Over the years, manufacturers have improved gas detection equipment to the point of including “bells and whistles” in a standard four-gas instrument. Somewhere in this is an oxymoron; the new definition of a commodity gas monitor includes some of the extras previously found only in industrial hygiene instrumentation. The danger in treating these life-preserving devices as commodity items is the general blurring of those features that are considered essential and those that are superfluous.
Listening to Customers
Often, in the “fuzzy,” front-end phase of new product development, gathering the voice of the customer provides great feedback for engineering design. However, more often than not, users want a multi-gas instrument to be packed with features and flexibility, yet small enough to be cupped in the palm of a hand.
Keep in mind that everything has a trade-off. The trade-off for longer run times is a larger instrument designed to accommodate a beefier power source. A larger display with simultaneous gas sensor readings requires a larger surface area, and therefore a larger housing.
With the new cell phone designs coming out every week, we all have been conditioned to smaller, lighter, cheaper (or free!) phones and to think twice about the commitment to purchase, because we know that something new is just around the corner. Cell phone manufacturers have succeeded at raising our expectations for innovative electronic designs. In turn, higher expectations have transferred to other electronic devices, including industrial hygiene instrumentation. Not only is more expected from the equipment – more is expected of those that manage and use it.
A true testament to hitting the mark on a great product is when consumers “upgrade” and pay for another version, even though the one they have still accommodates their needs. Gas monitor owners face this decision each time a new model is released with yet another bundle of features. Many of the new functions are designed to improve user friendliness, reduce ownership costs and liability and increase product reliability. Sometimes, however, it is hard to determine “fluff” when reading the manufacturers’ information.
The debate now has become who determines whether something is labeled as nonessential versus critical when it comes to gas detection. The answer, of course, is you, the end user! As consumers of gas detection equipment, you are best-qualified to determine what features and functions suit your needs. Having said that, if the choice is left up to you, you need to be well-educated about gas monitor features and options as well as the limitations created by technology and intrinsic safety requirements.
Sensor Options
Over the course of the years, sensor miniaturization and advanced signal processing have enabled manufacturers to use a mix of sensor technologies in the same package to accommodate the best total solution for environments with multiple gas hazards. This adaptability reduces operating costs and training expenses. “Smart” sensors come pre-calibrated and include on-board data specific to that particular sensor, including sensor type and measuring range, calibration set points and unique serial number identification.
Another feature – sensor overrange protection – uses the power of the microprocessor and the sensor signal processing to electronically shut off power to the sensor after reading high levels of gas, which extends the life of the sensor, ensures sensor integrity and lowers replacement costs.
User-Configurable Operating System
User-friendly programming of the operating system allows managers to “tune” the instrument to their specific applications for display choices, alarm parameters, calibration settings, data management and other instrument operations. Password-protected codes restrict users from tampering with settings established by industrial hygienists or safety managers.
Display Advancements
Advancements in LCD display technology offer options well-beyond what older, eight-segment LED displays could provide. Improvements in the user interface of consumer products, such as cell phones, have spilled over into gas monitoring instrumentation.
One of the recently released gas monitors has the world’s first full-color display. Although technically difficult to accomplish with a color display, the unit is certified intrinsically safe. The benefits of a color, graphic display include readability in any lighting, intuitive interpretation with color-coded visual signals and clarity with detailed data graphs.
Gas detectors display as much, or as little, information as deemed necessary. Worker efficiency and skill level may determine a manager’s decision to activate a text-only versus readings mode. Some instruments have the ability to activate a text-only display for the end user while at the same time having the more advanced features working in the background for industrial hygiene uses.
Some of the newest monitors even have on-board graphing capabilities of the real time and peak readings. Newer graphic displays with icon-driven or language-selection menus allow a multi-lingual work force to use one common instrument, minimizing training issues associated with language barriers.
STEL/TWA Calculations and Peak Readings
One of the main keys to the progression of gas monitoring equipment centers on its ease of use, particularly relating to the calculation and documentation of industrial hygiene data. STEL and TWA readings are calculated and displayed in real time, providing managers with precise measurements for occupational health assessments. A peak/hold function allows professionals to show peak exposures during job functions at the end of a work shift or after a monitoring incident has occurred.
Data Logging of Gas Exposure Data
In addition to STEL and TWA, data logging typically captures each gas sensor reading, temperature, instrument ID and time and date of the sample. This is valuable tracking information the instrument can provide to occupational environmental health and safety (OEHS) professionals to maintain accurate records and documentation so they are within safety regulations.
Previously an optional add-on, data logging features typically now are included in the base price of a monitor. Microprocessor-driven designs allow built-in or removable data storage to provide days, weeks or even months of extended-shift, continuous data recording before exceeding memory capacity. Through easy operating system setup, managers can program data logging intervals, pause and resume choices and overwrite capability and automated event logging. Accompanying downloading and graphing software provides an analytical tool for the industrial hygienist or OEHS manager.
Data Input Element
A data input element further enhances the logged data to imprint the data logger with user and location/site information automatically. One benefit this provides is the means for validating gas survey data through identification and time/date stamp of each monitored site, user and gas measurement/exposure record. Field data input can be achieved manually or be automated by scanning bar codes or memory devices carried by the user or attached to the site being monitored.
Power Sources
Most monitors offer a variety of power sources to provide round-the-clock monitoring capabilities, as well as alternate battery power available at a moment’s notice. The latest rechargeable battery technologies, such as lithium-ion, do not have the “memory” problems found in older nickel-cadmium batteries. New, non-rechargeable lithium batteries typically are smaller in size, lower in power consumption and provide extended instrument run time allowing for lasting power throughout long shifts for continuous worker protection.
Alarms
Audible, visual and vibrating alarms provide the user of the equipment with an indication that dangerous conditions exist. The combination of all three types of alarms built into the instrument is possible with the new power options available today. It is important that the audible alarms are intense, the visual alarms bright and capable of being seen from a wide angle and that a vibrating alarm is strong so that they grab the user’s attention immediately when an alert is necessary. Usually a selectable option within the operating system, high alarm levels “latch” on to ensure a warning is not ignored and the user acknowledges the danger. Latching alarms cannot be turned off unless the atmosphere is clean and conditions are safe.
Calibration Options
There is no electronic method for compensation or a full self-calibration of sensors that will correct the effects of drops, shocks or extreme exposures to gas or temperatures. The importance of regular instrument calibration is critical to prevent inaccurate readings. Today, most direct-reading instruments offer quick, push-button calibration with electronic corrections in place of older, potentiometer adjustments.
With the latest operating systems, many instruments provide the option to track and display the last calibration date or the next date the instrument is due for calibration. This feature allows the user to be certain that the instrument has been calibrated and maintained within an acceptable timeframe.
Automated Maintenance
Automatic instrument management stations, or “docking” systems, quickly have become a very popular trend in the gas detection market. These systems are designed to automatically maintain the instruments by bump testing, calibrating, downloading hygiene data, testing integrity and charging the instruments automatically with no need for end-user intervention. Additionally, some manufacturers offer service options that remove the burden and liability of instrument maintenance and calibration.
The next time you are in the market for a gas monitor, consider your needs and start by reviewing the specifications and third-party certifications. We’re all guilty of being swayed by a certain feature that appeals to us, even if we are well-aware that it is frivolous and unnecessary.
Take a moment to ascertain what your true requirements are, identifying which features are critical, and which are simply “bells and whistles.”
Kay Mangieri is responsible for planning and directing all marketing functions for Industrial Scientific Corp. Mangieri received her M.S. degree in industrial administration, marketing concentration, from Carnegie Mellon University prior to joining Industrial Scientific in 1992 as customer service manager. She has been a member of the American Marketing Association since 1991. She can be contacted at (800) 338-3287, or via e-mail at [email protected].