 Industrial hygiene surveying. It's become an important part of preventive medicine. This film deals with equipment and techniques you'll be using for the surveying of physical agents. Sound, heat, and light. A second companion film, which you should also see, deals with surveying chemical agents, gases, vapors, and particulates. The techniques of industrial hygiene surveying can be broken down into three phases. Recognition, evaluation, and control. These two films are primarily concerned with the recognition and evaluation phases. The recognition phase begins in your own office, even before you've arrived at the inspection site. Good morning, Tom. Good morning, sir. Did anything come up while I was out of the office yesterday? Yes, sir, we've got two requests for industrial hygiene surveys. This one from the post-laundry and this one from the drafting office. Okay, have you seen either of these two places, Tom? No, sir, I haven't. Okay, I haven't been to either of these places either. You take the drafting office and I'll take the laundry and check in the files and see if you can find any additional information on what equipment they have and what kind of materials they'll be using there. All right, sir. From the records of prior surveys, you can learn a lot about what kinds of hazards to expect, what problems were discovered earlier, and what corrective steps were taken to control them. And you also want to have a thorough understanding of the work itself, raw materials, by-products, job classifications, and so on. From among the many industrial hygiene reference materials available, the industrial hygiene evaluation guide can answer many of the questions you have on procedures and techniques of the survey. The fact is, to conduct a thorough survey is no simple job. It calls for a lot of thought and planning in advance. Next step in the recognition phase is the preliminary survey. You're here largely for planning purposes. To find out what measurements need to be taken, what equipment you'll need to bring, you want to observe the operations and the chemicals being used, the work practices, the protective devices, and the like. At the same time, you want to gather general information and find out if any changes have occurred. And you want to see whether the supervisor and the workers are familiar with the safety requirements and are following them. Mr. Johnson? Yes. I'm Lieutenant Booth, and this is Specialist Howard. How are you, sir? We're here from the Preventive Medicine Office, and we're here to perform the industrial hygiene survey that you requested. Okay, have a seat. First, we'd like to ask you some questions about the operations here, and then we'd like to take a tour of the facility and have you explain the work processes as we go. Okay. Approximately how many employees do you have working for you here? Well, we have right now, full strength is 67, but without the temporary hire, we employ 55 full-time employees. Are you aware of any work-related illnesses here? No, not since I've been here, I haven't had any complaints. Okay. Just what were the work or complaints that you referred to in your request to us? It was mostly the noise area around the boardroom and around the washdeck, then your heat in the back of the laundry, and then around the flight work owners in your pressing day. Oh, okay. Well, let's go ahead and take a tour of your facility, and you can explain the operations as we go then. Okay. You'd like to follow me? Okay. You should have an escort during the preliminary survey. The supervisor or someone he appoints. But work things out so the supervisor doesn't intrude when you're talking to the workers. You want honest answers, and you may not get them if the boss is listening. Get the workers' view of health hazards, environmental work conditions, and safety practices. Also, find out if the workers know what protective devices are required and use them when they should. Obviously, if you have problems conversing over the ambient noise in any area, the sound level probably exceeds the standards. Spend enough time on the survey to become thoroughly familiar with every phase of the operation. This is important. It's the only way you can find out what's really happening. The preliminary survey is the time when you gather data to decide what measurements you'll be taking during the actual survey. Chemical fumes, temperature, noise, ventilation systems. There's a lot to consider in a facility like this one. By contrast, the survey of the drafting room will take much less time to accomplish. The purpose of industrial lighting is to provide efficient performance of visual tasks, and to help provide a safe working environment. A question has been raised about whether the drafting tables are getting a proper amount of light. So your team will conduct a survey to evaluate the light levels. Be sure to note the type of general lighting, as well as any supplemental lighting. On return from the preliminary survey, you review your notes, determine what equipment you'll need, and get it ready. The equipment you use may differ somewhat from the types you see here. But the general principles are the same. Most of the instruments require some kind of checkout or calibration before each use. Until you're thoroughly familiar with a particular instrument, refer to the instruction manual. Here's the sound level meter you'll be using for noise measurements at the laundry. The batteries can be checked simply by turning the instrument on, pressing Battery Check, and seeing that the needle swings into the region marked Battery. To calibrate the instrument, you use a separate device. The sound level calibrator. Turn it on and make sure its battery light appears, indicating that its batteries are okay. Then turn the control knob to the first frequency setting. 2000 hertz. A raucous tone like this means you have to hold the control knob in the start position a little longer to get the oscillator going. This is how it should sound in the 2000 hertz position. Now using the appropriate microphone adapter, mount the calibrator on the sound level meter. For calibration, make sure the meter is set on the C scale and slow response. For each of the five calibrator frequencies, note the meter reading. During the survey, the meter will be set on the A scale, slow response. The A scale is designed to hear on the same curve as the human ear, and OSHA regulations require measurements to be taken on this scale and slow response. In the calibrator instruction manual, there are correction tables that should be used if you have to correct for atmospheric pressure in areas of high altitude. The calibrator itself must be checked for accuracy once a year by an authorized lab. The inspection sticker will show you if the instrument is still current. Neither of the other two instruments that will be used today require much in the way of pre-survey check-out. The light meter measures, in foot candles, the quantity of light striking the meter. For the wet bulb globe temperature kit, all that's required is making sure that the thermometers are working order and bringing along a small quantity of distilled water. When the preparations have been completed and all the instruments checked out, you're ready to begin the second phase of the surveying techniques. Everything's packed up and ready to go. Okay, real fine. First thing tomorrow morning, we'll go over to the laundry. Be sure and wear your fatigues in in the morning. We'll take the equipment with us at that time. As long as we're going out anyway, should we take the light meter with us in the morning office at the same time? Yes, that would be a good idea. Time is almost over. You begin the evaluation phase of the survey at the inspection site. Temperature monitoring sites are selected from among areas suspected of producing heat-stressed problems. You then prepare the wet bulb globe thermometer kit by wetting the entire wick with distilled water and filling the reservoir. Set up the instrument and allow time for the readings to stabilize. Allow about a half hour for the first reading and five to ten minutes for the ones after that. You're trying to determine the heat stress on the workers, so take your readings near where the workers are. When you're taking sound-level measurements, you begin on the 1-10 to 1-20 dB scale. The meter is set on the A-scale and in slow response. Readings are then taken in areas that the workers frequent. Adjust the dB scale if necessary until a reading is obtained. The location where the reading was made and the reading are noted and recorded. You need to take several readings at different locations to get a true indication of the problem. Notice that you hold the meter so that the microphone does not point toward the noise source, points at right angles to it. Make sure you take a reading at any area where the worker spends a lot of his time. Take the reading close to the worker so that you measure the noise as he actually hears it. Position the meter so that it is between the worker and the noise source and so that it is not being blocked by your body or the workers. By now, it's probably about time to take your first series Since in this case temperatures are being taken indoors you're only interested in reading two of the three thermometers the wet bulb and the black globe. Later, you'll combine these readings to determine the WBGT index value. During the course of the survey you continue to take other temperature readings as appropriate. In particular you're interested in the worst case situations. That is, work areas where the heat and humidity are probably the worst. A large workspace may require several readings. Upon your arrival at the drafting room you'll want to make a diagram of the work area, indicating locations where the light measurements will be taken. Colors, reflectances and condition of room surfaces are all items that you should also consider in your evaluation. The procedure for measuring the light levels is straightforward. Place the light meter on the work table or desk. Note and record the reading. When moving the meter from one area to another it may be necessary to shift to a different sensitivity range. The reading is given in foot candles. Before you're finished you'll take similar readings at each work area in the room. The field surveys have been completed it's time to do your calculations and interpret your data. In particular you want to find out how your results compare with previous surveys of the same location and with the standards as set up by Army regulations, OSHA and others. This is the final step in the evaluation process. If any hazardous situations are uncovered your report must include recommendations to control them. The specific control measures applied must be chosen as the most suitable for the particular situation. The final phase of the surveying technique is control. A few of the possible controls at the laundry might include improving the ventilation either generally or at the work station. Isolation of the heat humidity source institution of a work rest regimen to shorten exposure time. There are of course many other possibilities. Part two of this motion picture deals with the survey techniques for chemical agents.