Environmental Standards Flashcards

Air temperature rises by 20°C during an EDM session and the ppm setting is never updated. What is the effect on measured distances?

Answer: A systematic scale error of roughly 20 ppm

A 1°C change causes about 1 ppm of error, so 20°C produces about 20 ppm of systematic scale error.

Which combined correction is applied to long sights in differential leveling?

Answer: Curvature and refraction, approximately 0.0206 K² ft with K in thousands of feet

The combined curvature and refraction correction is about 0.0206 times the square of distance in thousands of feet.

Riparian buffer requirements most commonly restrict development within a set distance of what feature?

Answer: Streams, rivers, and other water bodies

Riparian buffers protect the vegetated land next to waterways to reduce erosion and pollution.

Under the Migratory Bird Treaty Act, what should a crew do if an active bird nest is found where brush must be cleared for a survey line?

Answer: Avoid disturbing the nest and notify the project environmental contact

The MBTA protects migratory birds and their active nests from take without authorization.

OSHA's heat illness prevention guidance for outdoor crews emphasizes which set of measures?

Answer: Water, rest, and shade, plus acclimatization of new workers

OSHA's heat campaign promotes water, rest, shade, and gradual acclimatization.

What is a Letter of Map Amendment (LOMA) used for?

Answer: To show that a structure on natural ground is above the BFE and remove it from the SFHA

A LOMA uses surveyed elevations to show that a property or structure on natural grade is not in the SFHA.

Why should a level or total stand be shaded from direct sun during precise work?

Answer: Uneven heating can shift the instrument's collimation and level bubble

Differential thermal expansion of instrument parts causes small but systematic pointing and leveling errors.