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Show Carefully drawn circuit diagrams, showing accurately the wiring color codes and terminal strip numbers, will save an immense amount of labor when a new technician is called in to service the equipment. A maintenance log should be kept for each instrument, showing the designated maintenance intervals and what is to be done, and logging the maintenance as it is performed. Careful, systematic maintenance will go a long way toward insuring reliable and accurate operation. Maintenance according to a regular, logged schedule is especially important for the type of seasonal observation which is done for avalanche purposes. Personnel often are on the job only during the winter months. There is a very strong tendency to drop everything in spring and not worry about maintenance until the first snow flies in the fall. By then there may not be time to do the job right, or a change in personnel will leave a complete maintenance gap unless an accurate log is being kept. Observation Site and Instrument Tower The snow and weather observations to be used for avalanche hazard forecasting ideally should be made at a common site which meets the following criteria: 1) Sheltered from strong winds 2) On a level surface 3) Easily accessible at any time of day or night h) Representative of snow and weather conditions at avalanche release zones All four of these criteria are seldom met by any one observation site. The most frequently neglected one is the fourth, because sites which satisfy this latter criterion seldom satisfy the other three. Accessibility is probably the single most important requirement, for even the most industrious observer will seldom maintain an accurate record if he has to travel a long distance to get the readings. It should be possible for the observer to^ reach the site in a few minutes at any time during day or night, without exposure to avalanche danger. The level surface is necessary to get decent snow depth readings free of errors from snow drift and creep pressures on the stakes. A slight departure from level is acceptable providing a 35 |
