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[Mike Willis]

I'm new here, so please let me know if I'm posting this to the wrong place...

I've been a volunteer sound guy at my church for the last six years. This summer I received several requests to run sound for outdoor events. Some are paid, some are volunteer. My question is simply this: are there guidelines, policies, or straight up information I can use regarding electrical safety for outdoor events, especially pertaining to inclement weather?

Many thanks!

[Mike Sokol]

I'm new here, so please let me know if I'm posting this to the wrong place...

I've been a volunteer sound guy at my church for the last six years. This summer I received several requests to run sound for outdoor events. Some are paid, some are volunteer. My question is simply this: are there guidelines, policies, or straight up information I can use regarding electrical safety for outdoor events, especially pertaining to inclement weather?

Many thanks!

Yes, this is the right place. And thanks for setting up your account with your real name as per the rules of this forum. I'm in the middle of setting up for a production/demo, but I'm sure others will be around shortly to answer your questions. But first, please describe the typical sound system you're talking about and your biggest questions. That will help prime the pump....

[Jonathan Johnson]

My question is simply this: are there guidelines, policies, or straight up information I can use regarding electrical safety for outdoor events, especially pertaining to inclement weather?

Some basic electrical safety tips for outdoor events:

• All outdoor electrical devices should be protected by a GFCI (RCD for those outside of the USA). The reasons are twofold: equipment used outdoors can be subjected to moisture which can cause electrical faults, and people are in contact with damp and conductive surfaces (the dirt) that provide a "better" ground path and, therefore, an increased shock risk if they come in contact with energized equipment.
• Anything that could become energized in the event of a fault (such as the metal framing of a stage, or a metal barricade) MUST be bonded to the electrical grounding system. This provides an alternate ground path for electrical faults, rather than having the electricity pass through a human. While these things aren't "electrical", people have been electrocuted when these non-electrical metal things have come in contact with abraded cords or other faulty equipment.
• If there is an electrical problem -- breaker or GFCI trips, or someone feels a tingle -- immediately disconnect the power and fix the problem properly. Do not attempt to override safety systems or "roll with it" -- that's how people die.
• If something looks out of the ordinary (but you're not sure), question it.
• Avoid powering separate pieces of audio equipment from separate sources if there will be audio interconnection between them. This can cause damaging current in the shields of the interconnects. (See next point.)
• Never lift the ground on the power supply (cheater plug) to eliminate hum or buzz. Instead, use an isolation transformer with ground lift on the offending audio interconnect.

There is a fair amount of discussion here regarding grounding of generators. Look for it; it's too much to fit in a bullet point.

[Mike Willis]

Yes, this is the right place. And thanks for setting up your account with your real name as per the rules of this forum. I'm in the middle of setting up for a production/demo, but I'm sure others will be around shortly to answer your questions. But first, please describe the typical sound system you're talking about and your biggest questions. That will help prime the pump....

Thanks, Mike. There are two typical scenarios. In the first, we're using an amp rack on stage powering passive speakers and monitors connected to an analog mixer at front of house with three to four wireless mics via 100' snake. Typical band setup: multiple singers, keyboard, guitar, bass, and drums.

In the second scenario, we're using powered mains and monitors instead.

In simplest terms, what should I do if I'm supporting an outdoor event and rain is in the forecast -- even a chance of rain?

[Mike Willis]

Some basic electrical safety tips for outdoor events:

• All outdoor electrical devices should be protected by a GFCI (RCD for those outside of the USA). The reasons are twofold: equipment used outdoors can be subjected to moisture which can cause electrical faults, and people are in contact with damp and conductive surfaces (the dirt) that provide a "better" ground path and, therefore, an increased shock risk if they come in contact with energized equipment.
• Anything that could become energized in the event of a fault (such as the metal framing of a stage, or a metal barricade) MUST be bonded to the electrical grounding system. This provides an alternate ground path for electrical faults, rather than having the electricity pass through a human. While these things aren't "electrical", people have been electrocuted when these non-electrical metal things have come in contact with abraded cords or other faulty equipment.
• If there is an electrical problem -- breaker or GFCI trips, or someone feels a tingle -- immediately disconnect the power and fix the problem properly. Do not attempt to override safety systems or "roll with it" -- that's how people die.
• If something looks out of the ordinary (but you're not sure), question it.
• Avoid powering separate pieces of audio equipment from separate sources if there will be audio interconnection between them. This can cause damaging current in the shields of the interconnects. (See next point.)
• Never lift the ground on the power supply (cheater plug) to eliminate hum or buzz. Instead, use an isolation transformer with ground lift on the offending audio interconnect.

There is a fair amount of discussion here regarding grounding of generators. Look for it; it's too much to fit in a bullet point.

Jonathan, thank you for this! Three more questions, then. First, what to do if the facility doesn't have GFCI? Second, what to do if the staging has NOT been grounded (and how can you tell?) Third, what's your policy about supporting events when rain is in the forecast?

Many thanks!

[Cailen Waddell]

Thanks, Mike. There are two typical scenarios. In the first, we're using an amp rack on stage powering passive speakers and monitors connected to an analog mixer at front of house with three to four wireless mics via 100' snake. Typical band setup: multiple singers, keyboard, guitar, bass, and drums.

In the second scenario, we're using powered mains and monitors instead.

In simplest terms, what should I do if I'm supporting an outdoor event and rain is in the forecast -- even a chance of rain?

That depends on your setup.  We are relatively rain tolerant.   Our setup includes a mobile stage that is wind rated and will keep gear dry.  The speakers are water resistant and weather treated.  So as long as there is no lightning or wind isn't blowing water into electrical equipment, we are good to go. 

Your mileage may vary....

I always recommend defining criteria for cancellation in advance.  having a designated weather monitor who gets to determine if cancellation criteria have been met also cleans up lines of communication. 

For example, we might say, blowing rain or lightning 15 miles or closer are our criteria.  If ether of them are met, we cancel immediately. 

Think about time to get gear and people safe and set warning criteria and distances appropriately. 

There may be times gear has to get covered and left in a storm.  Be prepared for that. 


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[Mark Cadwallader]

GCFI devices are available in "stand alone" forms. Short (2') triple-tap 12/3 cords are the most common. Plug-in single recepticle devices are also available, as are replacement NEMA 5-15P plugs with a GFCI that are installed on a power cord.  Electrical supply houses have them, as do "big box" home improvement stores.

[Erik Jerde]

Forecasts can go all sorts of ways so events usually (never in my experience) are called off just do to a forecast.  Actual weather and solid decision points are a good thing to have.  As for your gear, be ready to bag it.  That can be tarps and/or large garbage bags with the necessary strapping and/or tie line to hold it all in place.  Have a plan on how you'll power down quickly too.  If your gear is elevated on stands have a plan to lower them quickly should strong winds show up.

Not a bad idea to have the tarps etc necessary to protect the band gear too, even if it isn't yours.

Consider equipment placement vis-a-vis flooding.

You can buy in-line GFCI units that you plug in between the wall and your extension cords/stringers.  Keep in mind GFCIs can trip due to unsafe equipment.  The musician will tell you it's "safe" and "has always worked fine elsewhere" and then they may attempt to throw you under the bus if you insist on keeping the GFCI.  Have a plan.

Off the top of my head, one way to check if the stage and other metal structures are grounded would be to use a DMM and meter from AC to the unknown metal thing.  If it's grounded your DMM should read aprox 120v.  If it's not grounded then no reading.  Of course meter the power to itself first to make sure you know what voltage it's supplying and that it's on.  May be better ways to do this, others will speak up on what they are.

With all the show stopping stuff (weather, gfci etc) make sure your plan is understood by the promoter and have their written approval/acknowledgement of it before the day of the event.

[Rob Spence]

Some thoughts...

I assume I need to ground the stage if it is metal. If someone else can show me it is already done, then good.

I provide all my own power cable. That way I know what I have. My power has GFIs at appropriate places. If one trips, I take that as a message that something is wrong. Sometimes it is obvious such as it got wet.

I have been purchasing weatherproof covers for the mains speakers I use outdoors. If there is a chance of rain, then the covers go on during load in.
I bring trash bags to protect stage monitors.
I place a tarp with the subs that can cover them with little work.
I have a large tarp behind the stage that can cover the whole thing. Just lay down the mic stands and spread the tarp.
I use plastic coated weights I have scavenged from exercise equipment to hold down pop up tents. I also have the side wall kit for my mix position tent and will start installing it if weather threatens.

I have a talk with the organizer about who calls a delay or cancellation while reserving my authority to cut power if I deem it a safety issue.

So, the message is, have a plan for what to do for each area in the event of weather. Have the tools available to deploy when needed. Make sure each crew member knows what their responsibility is when it is time.



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[Stephen Swaffer]

Off the top of my head, one way to check if the stage and other metal structures are grounded would be to use a DMM and meter from AC to the unknown metal thing.  If it's grounded your DMM should read aprox 120v.  If it's not grounded then no reading.  Of course meter the power to itself first to make sure you know what voltage it's supplying and that it's on.  May be better ways to do this, others will speak up on what they are.

Because this can be life and death and because I think using proper terminology leads to better understanding and practice I will make the arguement that I don't really care if the stage/metal device is grounded-I do care very much that it is bonded to the electrical service-and that all seperately derived services are also bonded to one common system that is then grounded with a grounding electrode.

The difference?  I can ground the stage by driving a ground rod connecting that to the stage with a piece of wire.

To bond the stage to the electrical service I need a metallic path (copper or aluminum wire, metal structural framing, etc.) between the metallic object and the grounding system of the electrical service.  This is critical for safety.

With that in mind, IMO, the best way to see if the stage, railing, whatever is bonded to the electrical service is to simply place an ohmmeter between the ground of the electrical service and whatever object you are testing.  If this is any higher than 1 ohm I would investigate.

Seperately derived services-a genny is a seperately derived supply.  A transformer (POCO or locally owned) supplying a service is a seperately derived supply.  Anytime there is a metal connection between the 2, the grounds need to be bonded.  Keep this in mind anytime your wiring might be the metal connection.

Not as difficult as it may seem.  Just keep the 2 terms-bonding and grounding seperate in your mind.  Each has a different purpose.  The code makes a big deal about this  for safety's sake.

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