Need Help With Unsafe Work Practices

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Hello everyone. I need some advice and maybe some training resources/videos on arc flash explosions.

I am an electrical engineer with 20+ years heavy industrial electrical experience. I am a new employee (2 months) to a company where it is common practice by management (including my boss) to bump 3-phase motors for rotation by opening up the MCC bucket door and use a screwdriver to manually close the motor starter. I've explained how this practice is rather unsafe and dangerous. The most commons response is, "We've done this for 20 years and nothing's happened. Besides, the breaker will protect me if something's wrong.".
The MCCs do not have HOA switches or Start/Stop pushbuttons (it's a DeviceNet MCC).

Any advice on how to successfully influence these guys and change their ways would be appreciated.

Thanks,

John
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
Re: Need Help With Unsafe Work Practices

I don?t know if it is possible to un-train a person who has been trained, through many years of experience, to accept a dangerous situation as being perfectly safe. My philosophical contribution, for what it may be worth, is something I learned from a previous employer. It is this: To fully and properly address safety, you must consider three things: (1) The probability of an accident, (2) The consequences of an accident, and (3) The cost (i.e., money, time, effort, etc.) of taking actions to reduce items (1) and (2).

Consider the ?game? of ?Russian Roulette.? One bullet in a six-shot revolver. Give it a spin, point it at your head, and pull the trigger. (1) The probability of an accident is 1/6, or about 17%. (2) The consequences of an accident is your immediate death. So let?s take an action to change the game a bit. Put one bullet in one revolver, and no bullets in another 99 revolvers. The game now is to select one gun at random, give it a spin, point it at your head, and pull the trigger. You have taken an action that has reduced the probability of an accident (it is now 1/600, or about 0.17%), but this action has not changed the consequences of an accident. The cost of this action is rather high: the price of 99 extra revolvers. Are you satisfied that you have taken enough actions?

The situation you describe very closely resembles the 100-revolver game. The probability of an accident is low, as demonstrated by the fact that no accident has taken place in the last 20 years. That does not mean that the probability of an accident is zero. And the fact that the probability is not zero necessarily means that an accident WILL happen, if you keep playing the game long enough. And look at item (2), the consequences of an accident: serious injury or death, and even a minor injury would expose the company to a lawsuit.

So what actions can you take, and what would be the costs of each action? One alternative is to stop playing the game (i.e., forbid the practice of manually jogging a motor by pushing the contactor). This might come at the cost of installing HOA switches for all motors, and might seem too high a price. A low-cost alternative is use an insulated tool (e.g., fuse puller), instead of a screwdriver, to reduce the probability of a slip-of-the-hand causing a short circuit. Another low-cost alternative is to wear appropriately rated and maintained insulated gloves, to reduce the consequences (with no change to the probability) of accidental contact with an energized surface. An alternative with only a slightly higher cost is to use a face shield, to reduce the consequences (with no change to the probability) of an arc-flash. Keep looking, and I?m sure you will find your way to other alternatives that the company can accept and that significantly improve the safety of all workers.

[ November 13, 2003, 11:54 AM: Message edited by: charlie b ]
 
Re: Need Help With Unsafe Work Practices

Thank you, Charlie B, for your very thoughtful and reasoned reply. I hadn't considered using face shields and insulated gloves, since my main goal was to get the practice stopped completely. However, since I probably (there's that word again) won't be able to get the practice stopped completely, perhaps I can adopt your face-shield & gloves suggestions.

I can also maybe get my boss to compromise on his unwillingness to use HOA switches and START/STOP pushbuttons by proposing a single three-positon JOG-OFF-REMOTE switch (with spring-return JOG to OFF operator) be installed on each MCC bucket door.

Still, if I can get my hands on some rather graphic videos of arc-flash explosions involving circuit breakers, fuses, contactors, etc. I think that might really help drive the point home. If people see what can actually happen to them if an accident does occur it might help educate our people to stop this practice altogether.

Suggestions anyone?

Again, Charlie B... Thank You very much.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Re: Need Help With Unsafe Work Practices

I can also maybe get my boss to compromise on his unwillingness to use HOA switches and START/STOP pushbuttons by proposing a single three-position JOG-OFF-REMOTE switch (with spring-return JOG to OFF operator) be installed on each MCC bucket door.
We use that idea except that the HOA is at the motor. The HOA is spring return to off from jog. The jog position bypasses all interlocks except for the overloads. The HOA is used to bump motors and other maintenance type activities, but the real reason they were installed is for the lockout process. The process requires that you go to the motor, jog it and see it run, go back to the MCC and lock it out and then return to the motor and try to jog it again. If it still runs you have locked out the wrong breaker!!
This process is called "Try-Lock-Try".
Don

[ November 13, 2003, 03:27 PM: Message edited by: don_resqcapt19 ]
 
Re: Need Help With Unsafe Work Practices

Thank you, don_resqcapt19, for your reply. I am very familiar with the Try-Lock-Try procedure and I personally think it's the best. I am going to try the JOG-OFF-REMOTE selector switch idea and see if I can sell it.

Any ideas on where to look for videos?

Thanks,

--John
 

gwz2

Senior Member
Location
Indiana
Re: Need Help With Unsafe Work Practices

Go to the www.bussmann.com site and read their Arc Flash subjects.

Buried in there some-where is a 5 page topic on " NEW for 2002. 110.16 Flash Protection Field Marking "

On pages two and five are some colored photos of mannequins being burned at open door MCC's.

gwz2

[ November 13, 2003, 04:49 PM: Message edited by: gwz2 ]
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
Re: Need Help With Unsafe Work Practices

Originally posted by ohioaviator: . . . perhaps I can adopt your face-shield & gloves suggestions.
Those were merely examples that I selected to convey the concepts of (1) Taking actions to reduce the probability, and (2) Taking actions to reduce the consequences. The RIGHT thing to do is to find out what ?Personal Protection Equipment? (PPE) is appropriate, then get you boss to buy it and to make everyone use it.

By the way, I'd love to award you two gold stars for your concern for safety, but I don't know how. So instead I'll give you two green smiles. :D :D
 
G

Guest

Guest
Re: Need Help With Unsafe Work Practices

gold%20star%20p3.gif
gold%20star%20p3.gif


It's been said before:, "in my [insert-years-in-field here] years of experience, I have never had a problem with [insert-problem-here], so it must not really be a problem-- and if it were, what's the worst case scenario?".

I believe most of us are playing Russian Roulette with about 1000-guns, but we're still playing the game. Some of us have a comfort range of 100-guns, but I'll shoot for 10,000-guns.
 

ty

Senior Member
Re: Need Help With Unsafe Work Practices

Try MSHA . You might be able to find arc flash videos there.
Here's a couple links I searched quickly on MSHA:
1 2 3
Here's a link to an article on IAEI's page. Scroll down to the link for 'Figure 3'.
And here's a link to an article on EC&M's page.
Hope this helps. TY
 

noxx

Senior Member
Re: Need Help With Unsafe Work Practices

this site has a collection of images from electrical accidents. They are quite frank and graphic, and certainly give one pause when we consider the little things we may or may not look out for everyday.

Images
 
Re: Need Help With Unsafe Work Practices

Hello All...

I want to thank you all for your helpful ideas and for pointing me to some very good training resources. I took a look at all of the photos, presentations, etc. and they will do quite nicely in getting the point across. I don't want to "gross out" anyone, but in this case I think that's what it's going to take to help educate our people to work more safely.

My responsibility doesn't end here, though. I've got to convince others up the line that it's in everyone's best interest to spend the extra few dollars on design and equipment features that will significantly reduce the probability of these kinds of accidents from occurring.

I believe I have enough info for now, but I'll check this thread from time to time for additional posts.

Again, MANY THANKS!!

John R.
Cincinnati, OH
 

hillbilly

Senior Member
Re: Need Help With Unsafe Work Practices

Good examples of why we need to plan and work safely. The life you save may be your own, or mine.
steve
 

friebel

Senior Member
Location
Pennsville, N.J.
Re: Need Help With Unsafe Work Practices

Good morning ohioaviator, I just happened to be going through the list of items, and I saw your message on a request for Safety.
Like you, I have been in the Industrial business for many years. I will tell you, if anyone did the practice of testing a motor rotation by pushing in the contactor with his screwdriver, he/she would be fired. I have had 600 volts blow up in my face. You only want it to happen one time if you live through it.
My recommendation of how to properly bump a motor for finding rotation, or for whatever reason.
1. You do it at the start/stop pushbutton station at the motor. Completely safe, and no danger to anyone.
2. There is an instrument, called a Biddle Phase Rotation meter. We use this all the time, especially on large motors. First you make sure that your phases in your starter are from left to right A -- B -- C --. Then you can put the Biddle Phase Rotation Meter leads onto the motor leads that you are checking for rotation.
You turn the motor shaft in the direction that you want the motor to run. You observe the needle on the meter, and if you are correct in your connections the needle with go to the right. If not correct, the needle will go to the left. A very simple operation, but extremely helpful, especially in the case of a large motor and high voltage. I am all for wearing safety equipment for doing electrical work, but in this case it is not necessary if you do it like I have suggested.
I worked for a large Chemical company who took Safety very seriously, and I am now retired. I am teaching in a Technical/Junior College, and I visit some plants for on-site training. It has opened my eyes to how some companies do not take electrical safety seriously enough. Let them have a fatality, and then in comes the OSHA team.
 

friebel

Senior Member
Location
Pennsville, N.J.
Re: Need Help With Unsafe Work Practices

To: ohioaviator, I forgot the part about having information on Arcblast pictures. I have always dealt with the Bussman fuse company, and they can help you out tremendously. I do not know your location, but if you want to em me privately, and give me your phone number, I would be happy to discuss this issue.
I also had Bussman come on to our site and they helped us out with Selective Co-ordination of our fusing. For example, at our plant, we use a lo-peak, dual element fuse, rated at 125 percent of the motor nameplate FLA. As you are aware the table in the code, Table 430.52 allows you to fuse at 175 percent. So as you can see, we have a better selective fuse ratio co-ordination.
 
Re: Need Help With Unsafe Work Practices

Hello Friebel,

Thanks for your reply. Our electrical contractors do have (and use) phase rotation meters. However, we still need to 'bump' motors for rotation during plant commissioning for several reasons. Indeed I would like to use local START/STOP stations for bumping motors... if we had them. For some reason, my boss (a mechanical engineer who's an electrical engineer wannabe) felt we didn't need local START/STOP stations nor did we need HOA switches and START/STOP pushbuttons on the MCC buckets. To further complicate matters, our MCC's are A-B Intellicenters with IEC components and DeviceNet overloads. In order to bump a motor somewhat safely we must have the PLC/HMI control system completely debugged and running. But without the motors test run, there's no way to completely debug the PLC/HMI system. It a vicious circle, aarrrgghh! But I digress.....

Again, thanks!
 

friebel

Senior Member
Location
Pennsville, N.J.
Re: Need Help With Unsafe Work Practices

To: ohioaviator, I had to respond to your last comment. You said, that your supervisor does not believe in having a start/stop button at the motor. What do you have at the motor to meet the NEC section, 430.102. I have never seen a motor installation without a start/stop button at the motor, and within sight of the motor, and no more than 50 feet of the motor.
Where I worked for 45 years, we even went one step better in the Locking & Tagging Procedure for motors. If you had a situation where you could not test the motor for bummping, due to an open, grounded, shorted, jammed motor, or the operations did not want you to bump the motor, we had installed a Test button, incorporated with the Start/Stop pushbutton station, that when you operated the Test button, it would illuminate a light, showing that the control circuit for that motor was still energized. You would then go back to the MCC and open the switch, pull the fuses, and lock and tag the switch. Then, back to the motor location and try the test button, and the test light naturally will not light, proving that you have locked out the right motor switch.
I am such a firm believer in Safety in Locking & Tagging, that I am going to give out my name and phone number, and em address, so that you may contact me.
Robert J. Friebel (Bob)
bobfriebel@verizon.net
(856)678-9003
 

iwire

Moderator
Staff member
Location
Massachusetts
Re: Need Help With Unsafe Work Practices

Originally posted by friebel:
You said, that your supervisor does not believe in having a start/stop button at the motor. What do you have at the motor to meet the NEC section, 430.102.
A disconnect switch is all thats required by 430.102

But that test button set up souds great. :)
 

greensky

Member
Re: Need Help With Unsafe Work Practices

a lot of good adviced has been given to you.I have nothing to add but this, as an engineer, we studied in University/college and then pass the board exam, In school we been train/educated for maximum safety that is why we have rule and codes(electrical).We learn to designed with maximum safety so that the user have max. safety, I am wondering why an engineer designed such as hazardous like that.May be that time it is strict as today,but today you have the power to changed the system for the good of the company and the personnel involve.

Always remember this: SAFETY FIRST BEFORE CONVINIENT AND PLEASURE...
 

big jim

Member
Re: Need Help With Unsafe Work Practices

I think the picture idea would help your cause a lot. Our facility used to mag stuff all the time. I was standing beside a MCC panel that tried to start with a 480 line-ground fault. Only controls for a 5hp motor. When the contactor pulled in, (normal run, not maging it) there was a real loud bang. The door held but there was no doubt that major nasty things had happened. Showing you people some real life results may do a lot more than all the lecturing/arguing you could ever do.
 
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