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Calibration stickers.

During surveys, I have seen items that require calibration and have stickers or labels that are damaged, incorrectly installed, or just plain missing. As difficult as it is sometimes to maintain calibrated equipment, it is very important that all personnel are trained on various calibration requirements. They must also know the meanings as well train junior personnel on the care and use of this equipment and what to do in the event these labels are damaged and/or missing.

Below are just the more common calibration stickers used onboard submarines. To see the complete calibration requirement instruction, review NAVAIR 17-35TR-8, Technical Requirements for Calibration Labels and Tags.

A. Calibrated (NAVSEA 4734/8, NAVSEA 4734/9 and NAVSEA 4734/10, and NAVSEA 4734/11) - This label (black lettering, white background) comes in three different sizes. It is the most commonly used label in the Navy METCAL program. It indicates that the instrument is within its applicable tolerance on all parameters and that there are no qualifying conditions for its use.

B. Special Calibration (NAVSEA 4734/14, NAVSEA 4734/15, and NAVSEA 4734/16) - There are three "Special Calibration" labels (black lettering, yellow background), differing in size and content. There is also a "Special Calibration" tag (NAVSEA 4734/6), which is used with the smaller of the two labels. The "Special Calibration" label is to be used whenever there is some unusual or special condition in the calibration, which should be drawn to the attention of the user and/or calibrator. The special conditions may be deviations from normal calibration tolerances, multiple calibration intervals, or a requirement for in-place calibration. The special condition requiring the "Special Calibration" should be described directly on the large label or on the tag when one of the small labels is used. Brief descriptions of the above special conditions include:

(1) Deviation From Specifications (limited calibration) - In cases where the user does not require full instrument capability, the calibration can be performed to reduced tolerances or cover less than all ranges and parameters. This approach is often used when the instrument does not meet full calibration tolerances on certain ranges or parameters but can still meet user requirements. On the other hand, the special calibration may be required to achieve a higher accuracy than usual on a short-term basis upon the specific request of the user.

(2) Multiple Calibration Intervals - Some instruments have components which require calibration less frequently than the rest of the instrument. For example, the attenuator in a signal generator may require calibration every 12 months, whereas the rest of the instrument parameters should be calibrated every 4 months. Since the attenuator calibration is time-consuming and may require unavailable standards, use of the multiple-interval approach can save considerable man-hours, as well as permit the more frequent calibration to be performed at a lower-level laboratory. When a specific instrument has been designated for multiple calibration intervals, such information is provided in the applicable calibration procedure. The "Special Calibration" label or tag is annotated with "Multiple Interval" and the type of calibration performed is indicated. The calibration due date reflects the due date of the next partial or complete calibration, as the case may be.

C. Calibration Void if Seal Broken (NAVSEA 4734/28 and NAVSEA 4734/29) - This label (black lettering, white background) comes in two sizes and is placed over readily accessible (usually exterior) adjustments to prevent tampering by the user when such tampering could affect the calibration. The label should not be used to cover adjustments or controls, which are part of the normal use and operation of the instrument. This label may also be used to prevent removal and/or interchange of plug-ins, modules, subassemblies, etc., when such removal or interchange will affect the calibration.
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Title Annotation:MMC (SS) Ingram
Date:Jan 1, 2012
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