Monday, December 26, 2011

1 Plus 1 Plus 1 = Hey, that's not such a good idea!

We've all done it. If you look around right now you'll probably see one, too. Plugging one extension cord into another extension cord may seem like a minor issue, but each time you plug stuff together you add a little more resistance into the power line. More resistance means more heat generated and more voltage drop at the far end of the cord. If the device(s) you are powering don't get the voltage they want, they may demand more current, and when they do that, then the heating in the cord goes UP and the voltage goes DOWN. Kind of a vicious cycle.

Relocatable Power Tap (Plug Strip)
It's not just Extension Cords, either, it's Relocatable Power Taps, too. A what!? Yeah, its a fancy term for a "Plug Strip" that UL uses.  Jim Hutchison's Blog JimOnLight has a great article about using RPT's safely, so go there to read that, and keep reading here for more Extension Cord Safety Do's and Don'ts.

So don't just think about the fully portable types like at left, you also have to consider the rack- mounted ones like this:
Rack-Mounted Relocatable Power Tap (Plug Strip)

Also note that a Relocatable Power Tap is intended only for indoor use as a temporary extension of a grounding alternating-current branch circuit for general use.

• Do inspect an extension cord for physical damage before use.
• Do check the wattage or current rating on the appliance or tool that the extension cord will be used with; do not use an extension cord that has a lower rating.
• Do make sure all equipment and extension cords bear the mark of an independent testing laboratory such as UL, ETL, CE, TUV, etc.
• Do make sure the plug on an extension cord is fully inserted in the outlet.
• Do replace an outlet (receptacle) if a plug is too loose and can easily fall or be pulled-out.
• Do match up the plug and extension cord on a polarized cord (one hole on the plug is larger than the other).
• Do keep extension cords away from water.
• Do use GFCI (Ground Fault Circuit Interrupter) protection when using extension cords in wet or damp environments or in areas considered construction sites like the scene shop and stage.
• Do keep extension cords away from children and animals.
• Do pull on the plug, not the cord when removing an extension cord from the outlet.
• Do store extension cords indoors (UV light damages the plastic casings).
• Do unplug extension cords when not in use.
• Do keep slack in flexible extension cords to prevent tension on electrical terminals.
• Do use cable pathways to cover cables passing through walk areas.
• Do use high temperature cord sets for stage lighting circuits.
• Do put safety covers on the unused receptacle outlets on extension cords.

• Don’t use an extension cord marked for indoor use outdoors.
• Don’t plug one extension cord into another.
• Don’t overload cords with more than the proper electrical load.
• Don’t run extension cords through doorways, holes in ceilings, walls, or floors.
• Don’t move, bend, or modify any of the metal parts of the extension cord plug.
• Don’t plug a three-prong into a two-hole extension cord.
• Don’t force a plug into an outlet.
• Don’t use an extension cord when it is wet.
• Don’t overheat an extension cord.
• Don’t cover an extension cord with anything.
• Don’t drive over an extension cord - especially with hard wheel devices like Fork Lifts.
• Don’t drag an extension cord.
• Don’t attach extension cords to the wall with nails or staples.
• Don’t run extension cords under rugs or carpets or in high traffic areas.

Other Resources:
Extension Cord Facts:
Underwriters Laboratory:
Power Strip:
Extension Cord:

Monday, December 19, 2011

Santa's Elves need to keep the workshop floor clear of obstacles

An elderly lady accompanying five members of her family to Santa’s grotto at a well known department store in London was injured during her visit, and the jury (not a team of reindeer) decided in her favor.  She successfully sued the events management company organizing the festive treat blaming Santa and his elf for failing to prevent her fall.

The grotto was operated by two employees, one who played Santa and the other an elf.  The elf escorted visitors in and out of the grotto whilst Santa sat on his customary throne entertaining his guests.  The elf and Santa both stated that they checked for loose items on the floor.  The injured lady's case was that she had lost her balance by stepping on a plastic icicle on the floor of the grotto which should have been seen and removed.

Santa and Elf leaving the Courthouse
Section 2 of the UK Occupiers’ Liability Act of 1957 required the events company to see that visitors would be reasonably safe in visiting the grotto.  This was found to not be the case.  The elf was concerned with many other duties – at a guess – toy-making and feeding reindeer perhaps!  It was found that Santa and the elf were not as careful in checking the floor as they should have been. If the icicle was there to be stepped on, it was there to be seen.

The overly benevolent view of the performance by Santa and the elf of their duties at first instance was overturned by the Court of Appeal who allowed the claim. Their checking of the grotto floor was held inadequate in protecting the public from falls.

Making a List, Checking it Twice!

Santa with his Safety Checklist
With claims against events holders attracting increasing publicity, this case highlights that the bar is set high for those responsible for carrying out hazard spotting.  Some guidance can be gleaned for events managers from the facts that have been touched upon in this case.  The main problem the events company could not overcome was the concern that time demands on their staff limited their attention towards taking precautions.  Staffing should be suited to the event in order to demonstrate that sufficient time and regard has been given to periodic checks, ideally being documented, as part of a documented risk assessment.  A higher standard of inspection is demanded for smaller areas such as this grotto, particularly in the context of the poor lighting present.

Employees need to be extra vigilant at all times, even in the season of goodwill to all men.

Be on the lookout for reindeer poo, too!  That could make you slip and fall off of the roof.

Saturday, December 17, 2011

Railing on and on

My friends at Simplified Safety posted an interesting blog entry at  It shows the use of Kee Klamps and schedule 40 pipe to build a guardrail on a theatre set.  It is a well-intentioned application, however, it also clearly shows that the set designer / constructor did not fully understand the building codes and OSHA requirements for railings.
Railing along upstage platform.
Railings are intended to prevent people and objects from falling over an elevated edge.  To be successful they must not only stop someone from falling over the edge should their center of gravity extend past the edge, but they must also prevent someone from slipping under the railing AND they must prevent objects from being knocked / kicked off of the edge.

  • The Upper Railing must be at least 42" above the platform (per International Building Code and OSHA). The railing in the picture scales to about 36" tall.
  • There must be a Toe-board (Kick-plate) that is 4" tall and the bottom of the Kick-plate must be no higher than 1/4'" above the platform.  There is no kick-plate present.
  • There must be intermediate railings or infill such that an sphere that is 21" diameter cannot pass through it (this limitation drops to a 4" if the railing is in a public place).  If the top of the top rail is at 42" and is 1.9" diameter, and the kick plate is 4" tall, then this leaves 36.1" of open space.  Installing an intermediate railing midway between the top of the kick plate and the bottom of the upper railing will satisfy this requirement.  There is no intermediate railing present.
  • Uprights for Railings must be in place ant no more than 8' intervals.  Just because you have a 20 foot piece of pipe doesn't mean that you can just install upright supports at the ends. The uprights in this application  appear to meet this requirement.
An additional requirement is that railing must support a load of at least 200 pounds pulling any direction.
  • Upwards:  Will it pull the railing right up out of the fittings or tear the bolts / pins / screws out?
  • Downwards:  Will it buckle and collapse under severe loading?
  • Sideways:  Will it collapse in a parallelogram?
  • Inwards or Outwards:  Will it support the weight of performers pulling or pushing on it, or falling against it, or leaning over it?
Kee Klamps can be a great tool to build frameworks, railings, platform supports, lighting towers, and many other elements in a theatre production.  As with any tool or fabrication, you must take the time to understand the building codes and do a structural analysis so that your finished product is strong enough to perform safely.

The Building Codes and OSHA do not differentiate between five seconds, five minutes, five days, or five years.  The objects you build, be they stairs, railings, platforms, or whatever must meet the requirements set forth -- regardless of how long they will be in service.

Well, at least it wasn't like this 8' unguarded drop behind the performer . . .

Friday, December 16, 2011

December is Fire Safety Month (yes, AGAIN)

The always vigilant writer Patrick Hudson at BackStage At has been after this one again, and he has some good words to read.
It hasn't been a pretty year for Fire Safety in Theatres:
It’s always a series of problems, not just one:
Twenty-Two Years, Multiple Theatre Fires:

Compartmentalize Your Storage:  Keep the fuel load to a minimum!
But don't do it like this:
Paint Storage Cabinet Made From Wooden Bookcase

Thursday, December 15, 2011

Pants on Fire!

Station Nightclub Fire - West Warwick, Rhode Island 2003
Most of us mere mortals never get to play Fireman in real life, so getting the opportunity to handle fire extinguishers, find-out about the adrenaline rush of putting out a fire, and experiencing the actual time constraints of a fire event up-close and personal doesn't come along too often.

This can change for all of us if we get together with our local community and make an effort to get Fire Extinguisher Training Programs set-up and active.  Most communities and fire departments cite the expense of recharging fire extinguishers as the main reason they don't provide this kind of training.  So, whats a wanna-be fire fighter to do?

Bullex Corporation decided that there needed to be a better way and they came-up with a training device that doesn't go through fire extinguisher powder.  It's call the Bullseye and it kind of looks like a flat-screen TV with a big remote control.  The screen is not a TV display though, instead, it is a computerized fire simulator that grows, glows, flickers, and dances just like a real fire (only without the heat and smoke).  At the base of the unit are special sensors that detect laser light that comes from a simulated Fire Extinguisher.

The Bullseye simulated Fire Extinguishers are pretty fancy units - not just a Wii controller stick.  They come in three sizes just like the real deal: 5 pound, 10 pound, and 20 pound; and they have a loudspeaker inside of them so you get that sense of whoosh! as they simulate a discharge.  Real nozzles, pull-pins, and squeeze handles, too.  They are even heavy like a real fire extinguisher.

The trainer sets-up the fire simulation to suit the type of training to be performed - they set the type of fuel and how big the (simulated) fire is going to be, and they say GO! (Or, maybe they don't say GO! and you have to figure it out for yourself - just like real fire.)

The system has a timer that keeps track of how long you take to respond and how long it takes you to put-out the fire.  And guess what?  If you use-up all of your fire extinguisher before you put out the fire -- it keeps burning.  D'OHP!  The system knows how much stuff you have to shoot and when it's gone, it's gone!  Game over.


Real fires don't have an OFF button, and real Fire Extinguishers only have a limited amount of fire fighting capacity.  IF YOU WASTE IT - YOU LOOSE.

PASS  - Know this phrase!
Pull the pin - this is so you are ready to do the job when you get to the fire.
Aim the nozzle at the BASE of the fire - if you point it somewhere else you will just waste the  fire fighting chemical.
Squeeze the handle - don't squeeze it until after you have aimed! (Just like a ketchup bottle)
Sweep the nozzle side-to-side along the base of the flame so you coat the fuel source with the chemical.

The cost of a training kit is about that of a small car, but if you spread that out over the whole community, it can approach a-dollar-a-head.  And there is no reason that the unit couldn't be used to train everybody from kindergarteners up to senior citizens.

Hands-on Training is the most memorable and effective training you can provide.  The community can make the rounds with this and see that schools, social organizations, community groups, and churches could all share in the benefits.  Training all of your performers and stage crew would be a high priority.  Maybe you can give them merit badges!  I'd say that if you didn't keep this thing busy at least 360 days per year that you were probably missing the point.

Dang, this is starting to sound like a Ginsu knife advertisement . . . however, one more thing that is interesting:  Bullex knows that this is a chunk 'o change to spend, so they rent the unit for test drives, too.  And if you decide to buy one within a year of the test drive, then they apply the rental fee to the purchase price.  Good Deal!

More info at:

Wednesday, December 14, 2011

Stage Truss Collapse in Italy Kills One, Injures Seven

2011-12-12, Trieste, Italy.  The concert trussing for a Jovanotti concert in the Palazzetto dello Sport an arena in northeastern Italy collapsed as it was being erected and a 20 year old student worker, Francesco Pinna, died from injuries sustained.  Italian news agency ANSA reported that rescue crews said the stage structure was nearing completion when the front buckled and collapsed, crushing workers below.  The accident took place at about 2 pm.  Around twenty technicians were erecting the stage, lighting, and PA system when the structure collapsed.   Rescue services intervened to take the injured workers to hospital.
Jovanotti Ora Concert Tour Stage Truss after Collapse in Palazzetto dello Sport

Police officers are now seeking to reconstruct the dynamics of the incident. Early reports say that the scaffolding “crumpled in on itself.”  Workers who were putting the finishing touches to preparations were overwhelmed by the collapse and some were trapped by steel tubes."

The concert has been cancelled and the remainder of the Ora Tour has been suspended pending investigation.  The sports complex in the San Sabba district, next to the Nereo Rocco football stadium, was seized by the authorities and cordoned-off. “All concerts have been suspended”, announced Maurizio Salvadori, owner of the Trident agency that manages the artist. “We’ll decide what to do tomorrow but at the moment no one wants to go on stage.  It is not known why the structure collapsed.  As always, everything was certified by an engineer. The structure was used all summer with no problems.”  Mr Salvadori explained that the “ground support”, scaffolding that carries speakers and reflectors, had given way.  The mayor of Trieste, Roberto Cosolini, hurried to the site of the accident and underlined the urgent need for “the investigations and expert reports to ascertain responsibility for this incident to be carried out with maximum rigour”.

“This tragedy takes my breath away. It struck me deeply.” Jovanotti tweeted his reaction to the fatal accident. “My grief goes out to Francesco Pinna, a student worker whose life came to an end today,” commented the singer, whose real name is Lorenzo Cherubini.  He added: “A tour is a family working to bring life and joy onto the stage.” A little later, the singer added: “The injured lads are specialised workers who do jobs they love while staying in the background. I’m with you. I love you.”

Tuesday, December 13, 2011

Power Play

Each year, thousands of injuries occur when an electrically powered tool or machine unexpectedly starts after a power interruption. This preventable hazard is caused when a tool's switch is left "ON" after a power outage, circuit breaker trip, or accidental unplugging from the wall outlet.  A button that locks the power trigger ON on many tools can become a dangerous feature when a cord is accidentally pulled from an outlet or a power drop-out occurs.  Drills, saws, grinders, sanders, and routers frequently are equipped with this 'feature' that can launch the tool off a workbench or across the floor when the power is unexpectedly restored.

The Safety GateProfessional Retrofit is a UL Listed, simple, low cost, safety product that attaches to your tool's power plug in seconds, providing restart protection wherever and whenever you use it.  It locks in-place using the tiny holes in the plug prongs, yet can be simply removed and used on other tools or stored away.

The Safety Gate™ works by recognizing when a tool's power switch is left "ON" and prevents power from being delivered to the tool.  The bright yellow LED indicator tells you that your SafetyGate is in "protect mode."  To reset it, you just turn the tool's power switch to "OFF".  It's completely automatic and there are no buttons to push or switches to reset.

The patented SafetyGate™ design complies with OSHA, NFPA, and CSA standards in eliminating the hazard of dangerous restarts. Hand tools and small machines can have the same safety restart protection that are mandated for larger industrial machinery.

More product information at:

Other related post:

Monday, December 12, 2011

ANSI Approves PLASA Dust Effect Standard

Luke, I'm Your Father
The PLASA Standards group has announce that on Friday, 2 December 2011, the ANSI Board of Standards Review approved the adoption of ANSI E1.40- 2011, Recommendations for the Planning of Theatrical Dust Effects, as an American National Standard.  The new dust effect standard is written as a recommendation, a document that gives a mixture of guidance "should" statements and mandatory "shall" statements.

A great variety of materials might be suitable for dust effects, either as dust lying on props and scenery or as aerosol clouds, so it does not specify exactly what dust must be addressed.  However, the standard will help people to avoid inappropriate materials, to select those that are least likely to cause health or safety problems, and to use them with care.  Publication is expected in a few weeks.