Diver sucked into power plant pump - Kentucky

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Diver would get stuck to grate, google Delta P.

Lockouts should be in place to prevent the pumps from being turned on. And all automatic systems related to the pumps should be disabled and locked out. Unfortunately some systems are so involved even those running them don't fully understand every possible way a system can turn itself on.

This is sad and tragic.
There are ways to make a grate to keep divers from getting stuck
 
Supposedly the Mansfield Dam dive park is safe, but some people are actually crazy enough to leave the park and penetration dive the dam's intakes.

Dive inside mansfield dam
Diving next to Mansfield dam near the jailhouse

I have no interest in ever, ever doing anything this crazy.
Thank you for digging up those threads, it makes me feel a lot better about diving in that general area. The visibility in that area is not great, and I was worried about accidentally swimming into a dangerous area if visiblity dropped to 1-3 ft (which it can in that lake). But it sounds like you'd have to deliberately swim into or near the "jailhouse" area, and/or ignore vibrations, etc. So long as I'm not intentionally swimming into those areas, I should be quite safe.

There are ways to make a grate to keep divers from getting stuck

This is correct, however dams are built to be dams, and not necessarily with the interests of a niche, like scuba-divers, in mind. Though having a dive-park right up against a dam seems like a dam(n) good reason to have those safety measures.
 
This is copy/paste from Scubadiving.com:

Typical water intakes around electric plants are built in such a way that water can flow all around an obstruction and not trap a diver. They have a cage built around the actual intake that allows water to flow in from the sides as well as the front, minimizing the suction that would prevent a diver from escaping.
 
Supposedly the Mansfield Dam dive park is safe, but some people are actually crazy enough to leave the park and penetration dive the dam's intakes.

Dive inside mansfield dam
Diving next to Mansfield dam near the jailhouse

I have no interest in ever, ever doing anything this crazy.

Some years ago I did a presentation for LCRA regarding the construction of the Marshall Ford Project (Corps of Engineer designation for the dam).

The intakes for the turbines is on the opposite side of the lake from the scuba park. The only time the "jailhouse" inlets are open are when there is significant flooding. In either case, for a diver to be in any danger you really have to want to earn your Darwin Award.
 
What a horrible way to go, very sad so young too.

One of my 1st attempts at commercial diving at the same age as the victim involved cleaning the intake screen at the former NE power plant in Mount Hope Bay Somerset MA. The intake was on, there was no way to go thru the screen but getting stuck to it was a real possibility. We used lines and harnesses but it was hold on or push away with one hand and scrape with the other. I lasted 2 days.
 
Lockouts should be in place to prevent the pumps from being turned on. And all automatic systems related to the pumps should be disabled and locked out. Unfortunately some systems are so involved even those running them don't fully understand every possible way a system can turn itself on.

Since this was a routine inspection of the pump impellers and intake shaft I assume the job was to be done with the pump off. You are absolutely correct in that the pump should have been locked out. However, only the main power source to the pump motor needs to be locked out. I'm assuming this was a 1200 VAC or higher voltage motor. These motors have large breakers that can be opened and racked out of a cubicle. There usually is a switch on the front door that must be pulled (opened) before the breaker can be lowered and racked out. This should be done after the breaker has been opened which is done when operations shuts down the pump. It makes no difference if the control circuits are de-energized or not, whether they are manual or automatic systems, or how simple or complicated they are. The only safe way to lock out equipment is to open a switch or breaker that feeds the motor itself. For 440 VAC breakers pulling the switch not only opens a circuit to the closing coil but also provides a mechanical interlock that prevents the breaker from physically closing even if there was a short circuit in the control system. For rack out breakers there is a physical separation between the energized side and the load side of the motor circuit that makes it impossible to provide contact to start the motor.

In the steel mill I worked in we had a pit outside that collected flume water which had scale in it. Occasionally, we would have divers go to the bottom and clear away the scale and debris that had collected around the pump intakes. This was a closed water system. To lockout a pump a trained electrical maintenance person would accompany the diver to the pump breaker. The electrician would verify the breaker was opened and then pull the switch. He would lower and rack out the breaker and would have the diver place his lock on the switch. The correct procedure was very detailed and specified in an SJP (Safe Job Procedure) of which the diver (company) had a copy of. Only the diver performing the job could put his lock and later remove it from the switch at the completion of the job.
 
Since this was a routine inspection of the pump impellers and intake shaft I assume the job was to be done with the pump off. You are absolutely correct in that the pump should have been locked out. However, only the main power source to the pump motor needs to be locked out. I'm assuming this was a 1200 VAC or higher voltage motor. These motors have large breakers that can be opened and racked out of a cubicle. There usually is a switch on the front door that must be pulled (opened) before the breaker can be lowered and racked out. This should be done after the breaker has been opened which is done when operations shuts down the pump. It makes no difference if the control circuits are de-energized or not, whether they are manual or automatic systems, or how simple or complicated they are. The only safe way to lock out equipment is to open a switch or breaker that feeds the motor itself. For 440 VAC breakers pulling the switch not only opens a circuit to the closing coil but also provides a mechanical interlock that prevents the breaker from physically closing even if there was a short circuit in the control system. For rack out breakers there is a physical separation between the energized side and the load side of the motor circuit that makes it impossible to provide contact to start the motor.

In the steel mill I worked in we had a pit outside that collected flume water which had scale in it. Occasionally, we would have divers go to the bottom and clear away the scale and debris that had collected around the pump intakes. This was a closed water system. To lockout a pump a trained electrical maintenance person would accompany the diver to the pump breaker. The electrician would verify the breaker was opened and then pull the switch. He would lower and rack out the breaker and would have the diver place his lock on the switch. The correct procedure was very detailed and specified in an SJP (Safe Job Procedure) of which the diver (company) had a copy of. Only the diver performing the job could put his lock and later remove it from the switch at the completion of the job.
I've worked in a couple of large facilities where we had to be in close proximity to high voltage or high power RF equipment and in both cases we used a system like this. Each of us had a key lock on the main breakers and it was impossible to access the hazardous area with the system powered on, and impossible to energize the system until all of the locks were disengaged. This is the proper way to do it, and the reasons it is done this way are hard-learned lessons of the past.
 
https://www.shearwater.com/products/swift/

Back
Top Bottom