NFPA 170 - FIRE SAFETY AND EMERGENCY SYMBOLS

Table 6.7.3 Symbols for Related Equipment

This is an interesting table, as there are (2) symbols with no descriptions, but I am only interested in the door holder symbol. In the past, for practicality, I have used a box with the letters DH in it, which is perfectly fine in my opinion (since that is what I have been doing anyway), but in an effort to maintain a close adherence to NFPA code, and its application to design, then one would want to use the symbol shown below. It is an unwieldy symbol in that there seems to be no logical orientation to it and the related door and wall, or door and floor. Nonetheless, I will incorporate the NFPA 170 symbol whenever possible.

Actual screenshot of page excerpt )table)

CAD block created for use in drawings.

NFPA 170 - FIRE SAFETY AND EMERGENCY SYMBOLS

Table 6.7.1 Symbols for Signal Initiating Devices and Activation Switches

All symbols used in Fire Alarm Designs drawings are derived from NFPA 170, however for what ever reason, there has been a flood of different symbols used for water flow and valve supervisory switches. This is understandable since there are different tables in this edition that seem to represent the same thing...but the actual table used is what should be taken under consideration. Below are examples of the symbols taken from Table 6.7.1, Symbols for Signal Initiating Devices and Activation Switches, as these appear to be the most appropriate for use in a fire alarm design
drawing.

actual screen shot of page excerpt NFPA 170

CAD blocks created from NFPA

these symbols are found in a different table,
Table 6.4 Water Supply and Distribution Symbols

SpeedCAD tips

Purge

The purge command, (icon looks like the head of a broom),
is an essential command to keep drawings organized,
reduce file sizes, and maintain performance. It is useful
after copying and pasting other objects from other drawings, since this operation can import many unseen elements to a drawing.
Purge the drawing to get rid of all unwanted and unused layers, line types,
font instructions, etc...All these things take up space, and also
can slow down the performance.
Autodesk article on purging unused layers. 

SpeedCAD

Types of Sprinkler Systems

Example Design Checklist

Example Design Checklist

____ Completed submittal application provided
____ Plans are clear and legible
____ A minimum of two and a maximum of three sets of plans and calculations provided
____ Plans are signed and dated by the RME (each sheet)
____ Calculations are signed and dated by the RME
____ North arrow provided
____ Common scale provided on the plans
____ Each room use is identified on the plans
____ Specification sheets for all devices (horns, smoke detectors, heat detectors, panels’ etc.)
provided
____ Voltage drop calculations provided
____ Battery drop calculations and discharge curves provided
____ Specifications for wiring (gauge etc.) provided
____ Information on type of conduit to be used provided
____ Riser diagrams provided
____ Wiring from device to device and end of line resistor provided on the plans
____ Total feet of wiring provided on the plans
____ Total feet of wiring provided from device to device
____ Legend for all devices provided on the plans
____ Device address numbers/letters provide on the plans for addressable or analog systems
____ Type of power, primary secondary etc. provided on the plans
____ Total number of each device to be installed provided on the plans (horns 22, heats 12
etc.)
____ Materials utilized in the specification booklet indicated by an arrow to identify the model
or part
____ Cross section(s) provided on the plans

Appliance Lump Sum, End Evaluation Method

Appliance Lump Sum, End Evaluation Method

NFPA 72 Handbook Equation
(1999)
• Appliance lump sum, end load evaluation:
Vload =Vterm − (Iload )(Rconductors)
Where:
Vload = minimum operating voltage of the appliance
Vterm = 20.4 (unless specified by mfr.)
Iload = Total Current draw of the connected appliances
Rconductors = total conductor resistance