When monitoring workers for personal exposure to noise or airborne contaminants, industrial hygienists have grown accustomed to dealing with the hassles associated with bodily-worn devices. Using tools like Casella’s Airwave™ App on a smartphone or tablet brings new levels of speed and efficiency to the entire sampling process.
Although noise dosimeters and sample pumps have become less bulky over the years and dosimeters have shed their cable mounted microphones, mounting these sampling devices on workers still entails a fair bit of finesse from the start, when the safety and health professional encroaches on the worker’s ‘personal space’ to affix the sampling unit to their clothing. Then they typically must press buttons to start the actual sampling run in order to minimize artifacts that would derive from having the device running before it is even mounted on the worker – this is especially true of noise dosimeters. To add further inconvenience to it all, every industrial hygienist (IH) knows that they will need to locate and interfere with the worker’s daily routine multiple times throughout the day when using personal monitors. Very few will ‘take it on faith’ and trust that the sample collection process is proceeding flawlessly. They will want to ensure that the proper flow rate has been maintained, the sample pump has not had to try multiple restarts due to some obstruction in the sample train, or in the case of a noise monitor, that the noise dose seems reasonable and not way out of the expected decibel range for that job description, which might indicate anomalies, artifacts or even tampering with the unit to influence the outcome of the test.
Now Bluetooth® 4.0 technology is transforming this daily routine into a far less intrusive and much more efficient process because an IH can use a tablet- or smartphone-based app for remote wireless control and review of instrument status – and even review exposure data ‘on the fly’. Imagine not having to interrupt a worker or stop them from performing their normal tasks just to know that the noise data appear valid or the pump parameters are operating within expected limits. Even the process of locating the worker wearing the device can be made more efficient – as the tablet app uses its Bluetooth signal strength indicator to know if the worker and the device are within 100 feet, even if the worker is not within the line of sight. (Note: This distance may not be achievable in all cases) Another example of increased efficiency comes from the reduced number of times that the worker must be made to ‘stand still’ while the safety and health professional checks, pauses, stops or interrogates the instrument manually to ensure that their sampling strategy is coherent with the worker’s routine (e.g. stopping or pausing a noise sample during breaks or lunch). Also, if ‘odd looking’ data or device status alerts are shown, it gives the IH a chance to query the worker earlier in the process and make adjustments if necessary to ensure valid data are obtained.
By reducing the number of ‘full stop’ interruptions from ‘many’ to only two (attaching the unit at the beginning of the shift and retrieving it at the end) the worker’s aggravation and annoyance factors are greatly decreased and the monitoring professional has a lot more time to carry out tasks that might otherwise have to take place at the day’s end. In fact, remote noise monitoring can effectively reduce the number of tasks that have to take place to document the exposure by removing a time-consuming step completely.
How is this possible? Let’s use the example of an IH who is tasked with gathering and reporting noise exposures on a group of workers at a remote operating site. Their goal is to obtain noise dose and TWA data on employees to determine whether or not they would be included in the company’s Hearing Conservation Program (HCP).
They travel to the site, incurring significant time and travel expense, and must sample as many workers as possible in just a few days’ time – with as close to 100% valid sample data as possible. And in addition to noise, they have plenty of other hazards to monitor, such as heat stress, arc flash, etc., and they’ll review confined entry procedures, check OSHA logs, meet with the staff and management plus other responsibilities. Now throw in some personal air sampling pumps to set up and calibrate, and maybe 5 or 10 dosimeters to hang each day on various workers and you have what amounts to an extraordinarily demanding set of tasks. And that’s before the day’s sampling data gets downloaded, reviewed, analyzed and documented.
By using a remote app to view and communicate noise dosimeter data, it’s possible to eliminate one time-consuming step – downloading and reviewing the data on a PC. Since the primary purpose of doing noise dosimetry is to measure and document the exposure level of each at-risk worker to know who must be in a hearing conservation program, (based on exceeding the OSHA Action Level of 85 dB(A) average sound pressure level for an 8 hour shift; equal to 50% of the allowable Noise Dose) these data should be permanently archived for proof of compliance to the HCP. Until now, that has required connecting dosimeters, usually one at a time, to a PC at the end of the day to download an extensive data file filled with the multiple averages, TWAs, Max and Peak calculations required by OSHA, as well as the entire time history memory of the dosimeter, which gives minute by minute or even second by second detail of the exposure. But all that downloaded data is ‘overkill’ if the employee was well below 50% of the allowable dose for the day.
From the above example, an IH may have seven noise dosimeters operating each day for four days, for a total of 28 workers sampled – and perhaps only two or three on any given day may show they are exposed above the Action Level. Since a remote data viewing app displays all the overall Averages, TWAs, Max and Peak data for an entire dosimeter run and can communicate this via email directly to your inbox (or that of a client or colleague) the need to download all of the detailed data to the PC becomes redundant. Even if each download only takes 1-2 minutes to execute, and another minute to review, annotate and store, the time adds up quickly. If five dosimeter results a day can be emailed directly from the tablet (with notes and even a picture of the work) in 30 seconds while still on site, you can accrue time savings of 15 minutes per day or more. Of course, the individual dosimeters still contain incredibly detailed data files which are available for download at any time for exposures that are over the Action Level. And with other available features like motion detection and .wav file event recording, artifacts and anomalies can be easily identified on high-noise level data records that allow the IH to know for certain if resampling needs to be performed.
The availability of smartphone and tablet apps like the Casella Airwave™ supplied with their dBadge2™ dosimeters and Apex2™ sample pumps represent a huge advancement not just in sampling efficiency, but increased accuracy of results and number of valid samples obtained. Time and money are saved – and potential for aggravation greatly diminished – a great example of how technology actually can make life easier!
Author: Rob Brauch, Casella CEL Inc.