please read the original post and then  respond to  sarahÂ
original post :
Electricity is used on all forms of construction sites. Most electrical work is relatively low voltage. Discuss what measures a safety professional could put in place to eliminate the hazards of electrocution, shock, burns, and falls. If you had to say one measure is more important than any other measure and, therefore, an employee can never forget to do that, what would it be? Include language that could be used in helping a new employee understand just what the big deal is about working with electricity.
sarah’s Post Â
This discussion went right along with my safety audit this week and focus for next week on reminding the trades that electrocution on jobsites was one of OSHA fatal 4 hazards and with wet grounds upon on us we need to more vigelient. Â While I walking the homes I noticed that an extension cord was pinched in the door from outside temp pole, so I unplugged the cord and was wrapping it up and then noticed that cord was damaged in several places, including around the plug. Â I tagged the cords and went down to site the next morning to talk to the guys about safety hazards I also had provided them with an article I found about extension cord safety rules. Â I changed the title trying to use a little scare tactic and called it 5 Simple Extension Cord Safety Citable Rules -I talked to them about the fatalities from damaged cords, pinched cords and trip hazard of cords running through doorways. Â My plan is to make additional flyers and with the dew and snow coming try to promote all trades to inspect extension cords, unplug and never plug in several cords, but get one that is fit for the job they need.
Reference
Konopelko, V. and Piekarski, P. (07/01/2016). Five simple extension cord rules to improve worksite safety. Occupational Health and Safety (OH&S). Retrieved from: https://ohsonline.com/Articles/2016/07/01/Five-Simple-Extension-Cord-Rules-to-Improve-Work-Site-Safety.aspx?Page=1
UNIT VI STUDY GUIDE
The Safety Issues Related to Construction of
Electrical Power Generation, Transmission,
and Distribution Systems
Course Learning Outcomes for Unit VI
Upon completion of this unit, students should be able to:
4. Recommend controls for addressing hazards at construction sites.
4.1 Explain the specific issues relating to Risk Assessment Matrices (RAM) and the electrical field.
4.2 Differentiate between routine hazards on general construction sites and the special hazards
found in the electrical field.
5. Apply safety management systems approaches to improving safety outcomes.
5.1 Present the specific issues related to the electrical field.
Course/Unit
Learning Outcomes
4
4.1
4.2
5.1
Learning Activity
Webpage: Recommended Protective Clothing & PPE by Hazard/Risk Category
Unit VI Research Report
Unit Lesson
Chapter 9
Chapter 11
Webpage: NFPA 70E Electrical Safety Standard
Unit VI Research Report
Unit Lesson
Chapter 9
Chapter 11
Unit VI Research Report
Unit Lesson
Chapter 9
Chapter 11
Webpage: NFPA 70E Electrical Safety Standard
Unit VI Research Report
Required Unit Resources
Chapter 9: Subparts K through O and Related Safety Practices
Chapter 11: Subparts V through Z and Related Safety Practices
In order to access the following resources, click the links below.
Industrial Safety and Hygiene News. (2019, January 3). NFPA 70E electrical safety standard.
https://www.ishn.com/articles/110023-nfpa-70e-electrical-safety-standard
Occupational Safety and Health Administration. (2013). Recommended protective clothing & PPE by
hazard/risk category.
https://www.osha.gov/dts/maritime/sltc/ships/shipboard_electrical/recommend_d6-d7.html
Unit Lesson
Almost everything runs on electricity in todayÂ’s world. Making that power and getting it into the hands of the
consumer is a herculean task. Each of the areas that will be discussed in this unit lesson has tremendous
significance for the safety professional. There are literally hundreds of textbooks and other resources
OSH 4310, Special Topics in Construction Safety
1
dealing with the issue of electricity, and because of that, this unit will deal specifically
with the GUIDE
construction
UNIT x STUDY
of said systems and how that electricity is used on the construction site. With that
Titlebeing said, letÂ’s plug in to
the issues.
Electrical Power Generation
The first issue for construction safety should be the generation side of electricity. Building power plants has
become a truly large-scale endeavor for the safety professional. There are so many different types of power
plants that any discussion, by its very nature, needs to be narrowed to the individual type of plant.
Wind turbine generators can be found almost everywhere in the United States. Offshore facilities are
becoming even more of an issue. Everything it takes to build a wind farm system on land now must be
marine capable. The turbines of yesterday are being dismantled and refurbished with taller and more
powerful turbines. The support systems
for these power plants—from the dirt work
to the collection systems for the energy—
each have significant hazards associated
with them.
Solar power systems have the same issues.
The big news in renewable energy comes in
the form of energy storage (Grossman,
2019). Large battery storage systems are
now in use and more are being planned.
Hydroelectric, coal-fired, natural-gas fired,
nuclear powered, and combined systems
are being constructed all over the United
States. Each generation of power plants
bring together all the construction trades in
one area. Trade stacking was discussed in
Hydroelectric substation
an earlier unit, and again here, it becomes a
(Vladwitty, n.d.)
hazard that must be dealt with. Think about
the construction of a single-family home and what trade professions are required. Now multiply that
exponentially and your risk assessment matrix will start to form. It is not uncommon to have 500 workers on a
single wind farm construction site. Hydroelectric generation construction sites could have thousands of
workers. There are going to be specific hazards that must be dealt with on each type of construction site for
each type of generation system.
Transmission of Electrical Power
Getting the electricity from the generation site to the consumer requires transmission systems. These can be
seen all over the countryside. Those lattice structures standing out in the fields towering several hundred feet
in the air with wires hanging from them are what is being considered here. Some of the newer technology has
spun concrete poles or steel poles. Imagine having to install just one of those. What types of hazards might
be found? In some cases, the transmission line system can run for hundreds of miles. A recent transmission
line built for both New Mexico and Texas stretches for more than 300 miles. One such proposed transmission
line from Wyoming to Las Vegas, Nevada, is more than 750 miles (Streater, 2013). Each pole must be
delivered to the site, a hole dug in the ground, the pole set, the attachment points installed, and the wires
connected. The crew for a transmission line can number in the thousands. The crew will work in all sorts of
weather conditions on all sorts of ground from desert to mountainous terrain and scattered over hundreds of
miles. Not long ago there was a proposal to install a transmission line system to connect all the Hawaiian
Islands together. On top of all the groundwork, that crew would also have to work on top of and under the
ocean. Most of the time with each transmission line system, there will also be substations and switch yard
stations that will be built. The safety professional will need to be well-versed in the specific hazard mitigation
systems for those construction sites.
OSH 4310, Special Topics in Construction Safety
2
Distribution of Electrical Power
UNIT x STUDY GUIDE
Title
Distribution takes the energy from the transmission line systems and brings it to the individual power
transformers found on the poles and transformer boxes located around oneÂ’s home. The original energy can
be as high as 500kV (kilovolts) or more and needs to be reduced to the 120V found in your home. The
distribution system helps with that reduction. Then the distribution to the service lines attach to your home
bringing that much needed electricity to the end user. Each step in the delivery of power from the generation
station to the outlet in oneÂ’s home requires construction professionals to build the system and repair or
replace as needed. When people talk of the infrastructure of a country, they are referring to this type of
system and others like roadways, railways, and waterways. It has been said that within the next 5 to 10 years
more than $20 billion dollars per year will be spent repairing and replacing the transmission and distribution
power systems in the United States alone (Rivera-Linares, 2016).
Preparing the Safety Professional
How does a safety professional plan for all the eventualities of building such a system? What methods can be
used to assist the construction safety professional in forecasting these hazards and finding ways to mitigate
those hazards? One such method might be the qualification standard found in the National Fire Protection
Association (NFPA), 70E (Industrial Safety and Hygiene News, 2019). This is a very good way to begin to
understand how electricity works and what hazards are found around electricity. Many safety professionals
already know about the Certified Safety Professional designation from the Board of Certified Safety
Professionals or the Certified Safety Manager certificate from the National Association of Safety
Professionals. There are others as well, including the Certified Utility Safety Professional designation from the
Utility Safety & Ops Leadership Network. Construction safety is one thing, but the construction safety issue for
building electrical energy systems is another altogether. There is a whole new layer of complexity to planning
for and implementing the safety management system for energy construction systems.
Specific Risks to Consider
One example of this specificity is the high-line inspector after the high-voltage conductor is installed on those
lattice towers or spun concrete structures. There are videos on the Internet showing what these inspectors do
(Intmensorg.com, 2010). They must fly in by helicopter sitting in the open doorway with their feet on the
landing skids. As they approach the wire, they must discharge the static electricity and then climb out of the
helicopter and sit on the conductor wires. The inspector then shuffles from one tower to another along the
conductor completing the inspection—all the while the conductor is energized with high voltage. That is one
job for one person. There are literally thousands of tasks like this on one of these systems.
Another such task would be the line puller. For a conductor to run from tower structure to tower structure, the
line must be pulled using a high-tension pulling system. Each tower will have a dolly, or pulley, attached at the
insulator so that when the rope is connected, the rope can be used to pull the wire. Each dolly must have the
rope placed into it using either a helicopter or a bucket truck with a worker (Rickunder, 2017). Once the rope
is run through each dolly, then the rope is attached to the wire puller. Tension is applied, and the wire is
pulled through the dolly systems. This wire is not energized, but that does not mean it stays that way. Should
the wire tension drop, the wire being pulled can fall onto other energized lines. Once enough wire is in the air,
the wind running across the wire can create a static electricity charge thus energizing the wire being pulled.
The serious issue here is the worker doing the pulling can be exposed to energy that must go to ground. If the
employee is that path to ground, injury or death can occur quite quickly. There are methods in place to
prevent these things from happening, but someone must be preparing for these issues and putting these
methods to use prior to beginning the task.
Personnel Issues
Linemen consistently fall into the top 10 most dangerous occupations in this country (Ward, 2017). Working
in and around energized equipment in substations is also highly dangerous. These professionals have their
own standards that must be met. The safety plan for a project cannot be a cookie-cutter type. Each plan
needs to be site specific and must address the hazards found in its own area. An example of this that is quite
simple is the use of high visibility retroreflective outerwear for the employees. If there is any potential of the
system being worked on becoming energized, then the PPE needs to be an insulating material and not a
conductive material—or not of a material that will melt when high voltage is applied. On most constructions
OSH 4310, Special Topics in Construction Safety
3
sites, this high-visibility clothing is made from standard polyester which will melt
under
high heat.
The
UNIT
x STUDY
GUIDE
standard for fire-retardant clothing comes into play when the employee could be
exposed to high heat from an
Title
energy source. This standard calls for all clothing from the skin out to the outermost layer to not have any
material that could melt under high heat conditions. Elastic in oneÂ’s socks or underwear cannot be worn in this
scenario (OSHA, 2013). When putting together a site-specific safety plan for these types of scenarios, one
must consider all possibilities.
Terrorist Activities
One other specific issue for the construction site dealing with these systems is the threat of terrorist activities.
Shutting down the electric grid can cripple an entire segment of the country. Security issues arise when
dealing with these systems. The federal government takes this type of terrorist activity seriously. Any safety
plan dealing with these types of construction activities needs to consider the ramifications of the interference
of power to the power grid and what that would mean to the country (Douris, 2018).
Construction Site Power Usage
One last issue for this lesson is the use of electricity on the construction site—not the energy sites listed
above but on the average building construction site. These are the places where temporary power posts are
installed so that the employee can charge their battery for the screw gun or circular saw, for the use of
extension cords and temporary lighting, and for getting heating and air conditioning into the areas under
construction as well as the wiring of generators and the use of grounding systems. A lot of thought is given to
the delivery of energy from the source to the end user on most major construction sites. Electrical poles are
set, and underground delivery systems installed. Temporary power stations are constructed and made safe
for the user. Systems to get the cords off the ground are purchased and installed. However, not all
construction sites have this type of forethought. The worker on that new house being built down the block
must use their portable generator with multiple extension cords attached. Maybe the ground fault circuit
interrupter (GFCI) works and maybe it does not. The cords may run on the ground through puddles of water
before entering the house. Then the cords are stepped on by all sorts of workers and run over by the wheeled
scaffolding. The cord may get damaged, exposing the conductors inside the torn outer covering.
One of OSHAÂ’s Focus Four Hazards is electrocution. Have you ever been electrocuted? That is a trick
question because electrocution is a cause of death. The worker is exposed to amperage that is enough to
stop the heart. Everyone knows that it does not take much amperage to do this (Peshin, 2017). Most
handheld electric power tools have 30 times the energy necessary to stop the heart. The electrical hazard is
taken for granted on many construction sites. Part of the risk assessment matrix for hazard identification and
mitigation needs to be the use of electricity on the jobsite. It does not matter how small or how large a jobsite
is. What matters is that the worker understands what their hazards are for that task and what is being done to
take those hazards away. In any normal site safety orientation, this topic is only covered briefly. Maybe some
form of lock-out/tag-out (LO/TO) instruction in provided, but in reality, most workers are given lip service on
this issue. Employees are so exposed to electrical hazards throughout their days on the jobsite and even at
home that they become insulated from the dangers of dealing with electricity. The safety plan needs to deal
with these issues in a complete way with the end objective being all employees understand the real and lifethreatening issues surrounding the use of electricity.
References
Douris, C. (2018, January 16). As cyber threats to the electric grid rise, utilities and regulators seek solutions.
Forbes. https://www.forbes.com/sites/constancedouris/2018/01/16/as-cyber-threats-to-the-electricgrid-rise-utilities-regulators-seek-solutions/#25e32434343e
Grossman, D. (2019, October 14). Are concrete blocks the next batteries? Popular Mechanics.
https://www.popularmechanics.com/technology/infrastructure/a29463165/concrete-block-energystorage/
Industrial Safety and Hygiene News. (2019, January 3). NFPA 70E electrical safety standard.
https://www.ishn.com/articles/110023-nfpa-70e-electrical-safety-standard
OSH 4310, Special Topics in Construction Safety
4
Intmensorg.com. (2010, September 11). The most dangerous job on earth: HVUNIT
cablex inspector
[Video].
STUDY GUIDE
YouTube. https://www.youtube.com/watch?v=oBJyyEAw-6g
Title
Occupational Safety and Health Administration. (2013). Recommended protective clothing & PPE by
hazard/risk category.
https://www.osha.gov/dts/maritime/sltc/ships/shipboard_electrical/recommend_d6-d7.html
Peshin, A. (2017, November 30). How much current can the human body withstand? ScienceABC.
Rickunder, G. (2017, July 7). Helicopter setting rope lanyard to pull new power line [Video]. YouTube.
Rivera-Linares, C. (2016, March 21). Transmission investment slow, yet steady at $20 billion per year.
PowerGrid International. https://www.power-grid.com/2016/03/21/transmission-investment-slow-yetsteady-at-20-billion-per-year/
Streater, S. (2013, July 3). BLM advances major Wyo.-to-Nev. project as Obama admin pushes renewable
energy. E&E News. https://www.eenews.net/stories/1059983876
Vladwitty. (n.d.). Hydroelectric high-voltage substation (ID 45762987) [Photograph]. Dreamstime.
https://www.dreamstime.com/stock-photo-hydroelectric-high-voltage-substation-svir-riverimage45762987
Ward, M. (2017, January 4). The 10 most dangerous jobs for men. CNBC Make It.
https://www.cnbc.com/2017/01/04/the-10-most-dangerous-jobs-for-men.html
OSH 4310, Special Topics in Construction Safety
5
