stairs should be installed between blank and blank degrees from horizontal

Stairs should be installed between 30 and 50 degrees from the horizontal, according to widely used safety and building standards.

Standard stair angle

• Workplace and industrial safety regulations specify that stairways must be set at an angle between 30° and 50° from the horizontal.

• This range balances safe footing, comfortable use, and efficient use of space in most buildings.

Common practice within the range

• Many residential and commercial interior stairs are often built in the narrower range of about 30°–37° for everyday comfort.

• Specialized stairs (such as very steep or ship-style stairs) may approach the upper end of the allowed 30°–50° range and feel noticeably steeper.

Answer to fill-in-the-blank:
Stairs should be installed between 30 and 50 degrees from horizontal.

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