What adjustment to the water supply is required?

According to Subtitle 4, Section 4-158 (k), The system supply shall be based upon the low hydraulic grade shown on the Hydraulic Information Sheet, as determined by the Washington Suburban Sanitary Commission (WSSC) or lowest hydraulic point per the water authority in areas not served by WSSC. The demand for the automatic sprinkler system must be below the available water supply curve, as follows:

  1. Automatic sprinkler demand plus 10% or 10 psi, whichever is greater for commercial systems under NFPA 13 and NFPA13R
  2. Automatic sprinkler demand plus 5% or 5 psi, whichever is greater for residential systems under NFPA 13D.

Show All Answers

1. Do I need a permit if I am modifying less than 10 sprinkler heads in commercial buildings and 6 or less in residential buildings?
2. Do you review plumbing drawings?
3. What are the fees for a fire alarm or sprinkler system?
4. What are the current editions being used for applicable NFPA standards and adopted codes?
5. What is the maximum distance allowed from the Fire Department connection to the nearest fire hydrant?
6. How do I schedule a Fire Inspection?
7. Do single family homes (one- and two-family dwellings) require automatic sprinklers?
8. Do I need to file plans for a sprinkler monitoring system?
9. Do I need to file fire alarm shop drawings to change a fire alarm panel?
10. What adjustment to the water supply is required?
11. When do I need to request a water test from Washington Suburban Sanitary Commission (WSSC) for my automatic sprinkler system?
12. Is the International Fire Code (IFC) adopted by the County?
13. Can the fire protection systems be reviewed under the Building Permit application?