
This legislation is huge - both in terms of benefits and implementation. This is part of the hidden costs of coal.
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Energy Information for the Volunteer State and Beyond
When you review your findings against the lighting plan, your suspicions are confirmed. Light levels really have dropped. In some places where the plan shows 45 footcandles, you measured only 25. In an inspection area that requires 90 footcandles, you measured 70. How can you figure out what’s going on?
A drop in light output is hard to isolate in time, because it tends to creep up on us. As light output diminishes a little each day, we adjust to the new normal. That makes troubleshooting more difficult, but not impossible.
Light output diminishes as lamps near end of life (the output curve varies by lamp type). So, maybe it’s just be time for relamping. However, there are probably other factors to correct. Things to check include: