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Thread: 2020 Fire Fighter Disco 1 & 2 Family Dwellings 230.85

  1. #21
    Join Date
    Dec 2007
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    NE Nebraska
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    If such requirement ends up happening, I'd like to see exception allowing for shunt trip main and remote switch for fire fighters. If they have to cut a lock before operating the switch, so what, they have the ability to do that.

    As far as spraying water on who knows what... direct stream is what has electrical continuity issues. To fight a fire direct stream is putting a lot of water in a small area, most of the time they are more likely to have wider mist pattern and not a direct stream, unless shooting the stream a long distance, but then allowing it to break up as it falls on it's target.
    I live for today, I'm just a day behind.

  2. #22
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    Feb 2003
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    Illinois
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    Quote Originally Posted by kwired View Post
    ...
    As far as spraying water on who knows what... direct stream is what has electrical continuity issues. To fight a fire direct stream is putting a lot of water in a small area, most of the time they are more likely to have wider mist pattern and not a direct stream, unless shooting the stream a long distance, but then allowing it to break up as it falls on it's target.
    Testing done by Purdue University for the US Navy a number of years ago, showed that even with seawater and a straight tip nozzle at 100 psi and 125 gmp, the current at the nozzle would be less than 5 mA at ~15' from energized 440 volt equipment. If the nozzle was set to a 30° fog pattern, the current was less than 5 mA at the nozzle ~2' from the energized equipment.
    The more serious water hazard for fire fighters is standing or flowing water in the floor or ground that is in contact with a power source.
    Don, Illinois
    (All code citations are 2017 unless otherwise noted)

  3. #23
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    May 2009
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    Quote Originally Posted by shortcircuit2 View Post
    New proposed section 230.85 requires a Emergency Disconnect for service conductors of 1 & 2 family dwellings located readily accessible outside the dwelling.

    Know as the "Fire Fighter Disconnected"

    Here is the language...

    230.85 Emergency Disconnects(s)
    For one- and two-family dwelling units, all service conductors shall terminate in disconnecting means having a short-circuit rating equal to or greater than the available fault current, installed in a readily accessible outdoor location. If more than one disconnect is provided, they shall be grouped. Each disconnect shall be one of the following:

    (1) Service disconnect(s) marked as follows: EMERGENCY DISCONNECT, SERVICE DISCONNECT

    (2) Meter disconnect(s) installed per 230.83(#) and marked as follows: EMERGENCY DISCONNECT, METER DISCONNECT, NOT SERVICE EQUIPMENT

    (3) Other than listed disconnect switch(es) or circuit breaker(s) on the supply side of each service disconnect that are suitable for use as service equipment and marked : EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT

    Markings shall comply with 110.21(B)
    Stupid proposal!

  4. #24
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    Mar 2003
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    New England
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    Quote Originally Posted by chris1971 View Post
    Stupid proposal!

  5. #25
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    Dec 2007
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    NE Nebraska
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    Quote Originally Posted by don_resqcapt19 View Post
    Testing done by Purdue University for the US Navy a number of years ago, showed that even with seawater and a straight tip nozzle at 100 psi and 125 gmp, the current at the nozzle would be less than 5 mA at ~15' from energized 440 volt equipment. If the nozzle was set to a 30° fog pattern, the current was less than 5 mA at the nozzle ~2' from the energized equipment.
    The more serious water hazard for fire fighters is standing or flowing water in the floor or ground that is in contact with a power source.
    Agree, how often is there something on the floor in a dwelling - I suppose extension cords but no permanent wiring.

    Around here you sometimes see center pivot irrigation sprinkler shooting right at 7200 volt to ground POCO primary lines or at transformer banks, nothing happens as it is not a direct stream.
    I live for today, I'm just a day behind.

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