Construction Safety

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Course Learning Outcomes for Unit

Upon completion of this unit, students should be able to:

2. Apply Occupational Safety and Health Administration standards and related practices to construction. 2.1 Identify personal protective equipment requirements for construction sites. 2.2 Describe fire-related OSHA requirements at construction sites. 2.3 Determine standards and work practices for safe use of tools. 2.4 Apply safe material handling standards and work practices.

4. Examine methods used to control common construction hazards. 4.1 Analyze hazards that contribute to construction accidents.

Course/Unit Learning Outcomes

Learning Activity

2.1 Unit IV Lesson Required Readings Unit IV Assessment

2.2 Unit IV Lesson Required Readings Unit IV Assessment

2.3 Unit IV Lesson Required Readings Unit IV Assessment

2.4 Unit IV Lesson Required Readings Unit IV Assessment

4.1

Unit IV Lesson Required Readings Unit IV Assessment Unit IV Assignment

Reading Assignment

Click here to access the OSHA Construction Industry Digest and read the sections indicated below.

Occupational Safety & Health Administration. (2014). Construction industry digest. [Brochure]. Retrieved from https://www.osha.gov/Publications/osha2202.pdf

- Air Tools, p. 10 - Belt Sanding Machines, p. 12 - Eye and Face Protection, pp. 23 - Fire Protection, pp. 26-27 - Grinding, p. 30 - Hand Tools, p. 31 - Head Protection, pp. 33-34 - Hearing Protection, pp. 34-35 - Jointers, p. 37 - Personal Protective Equipment, pp. 43-44 - Powder-Actuated Tools, p. 44

UNIT STUDY GUIDE PPE, Fire Protection, Material Handling, and Tools

https://www.osha.gov/Publications/osha2202.pdf

UNIT x STUDY GUIDE

Title - Powered Industrial Trucks (Forklifts), p. 45 - Respiratory Protection, p. 48 - Saws, pp. 50-52 - Storage, p. 62 - Water, Working Over or Near, p. 64 - Woodworking Machinery, p. 67

Click here to access the Construction Industry Outreach-Trainer Presentations and view the Presentations listed below.

Occupational Safety & Health Administration. (n.d.) Tools—hand and power [PowerPoint presentation]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Occupational Safety & Health Administration. (n.d.). Personal protective equipment [PowerPoint presentation]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Occupational Safety & Health Administration. (n.d.). Materials handling, storage, use, and disposal [PowerPoint presentation]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Read the Student Handout below:

Occupational Safety & Health Administration. (n.d.). Construction focus four: Struck by hazards [Brochure]. Retrieved from https://www.osha.gov/dte/outreach/construction/focus_four/struckby/struckbyhaz_handouts.pdf

Unit Lesson

Cartoon depicting the importance of safety (Almeida, n.d.)

What do all construction worksites have in common? Certainly, they all need to comply with the Occupational Safety and Health Administration (OSHA) construction standards, but at an operational level, one common characteristic is that they are constantly changing. New processes are started as the project enters a new phase, and some processes end. Each new process introduces new hazards that must be identified and controlled. Fortunately, we can anticipate many of the hazards that are likely to arise in most construction activities. The OSHA construction standards provide a good starting point. In this unit and the remaining units in the course, we will use 29 CFR 1926 to guide our study and understanding of common construction hazards.

Personal Protective Equipment

A basic principle of hazard control is that personal protective equipment (PPE), such as eye protection, hearing protection, and head protection, is to be used only when engineering controls are not feasible (Asfahl

https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

https://www.osha.gov/dte/outreach/construction/focus_four/struckby/struckbyhaz_handouts.pdf

UNIT x STUDY GUIDE

Title

& Rieske, 2010, p. 57). The changing nature of construction sites makes it difficult, if not impossible, to isolate hazards from workers. Painters, while not creating noise themselves, may be working in close proximity to carpenters using power saws. Electricians may be working near painters and exposed to paint vapors. Still, making PPE use mandatory for all employees must be done judiciously. PPE can be uncomfortable, and wearing it all day might result in its removal at a time when it is most needed. It is also important to note that a single item of PPE may not be adequate for all degrees of a hazard. If you give painters paper dust masks because that is what the carpenters are using, the painters will not be protected against exposure to organic vapors. Likewise, while safety glasses with side shields may be adequate for workers using hammers to nail roofing shingles, they would not be adequate for workers using grinding wheels—additional face protection is needed. For all types of PPE, OSHA requires that employees be trained in the correct use, maintenance, and storage (OSHA, n.d.-c). When PPE is required, its use must be actively enforced at the worksite.

Fire Prevention and Protection

There are many sources of fire on a construction site. Welding operations, temporary electrical wiring, gasoline-powered generators, and temporary heaters are all sources of ignition for the wide variety of flammable and combustible materials that are stored or used. For this reason, OSHA requires that portable firefighting equipment be available on all construction worksites and that employees are trained in its use (OSHA, 2014). Fire extinguishing equipment must be distributed so that employees do not have to travel more than 100 feet from any location on the site to a functioning extinguisher. Welding operations may require a hot work permit and a fire watch. Additional fire prevention requirements can be found in the sections of other 29 CFR 1926 standards such as Subpart D, Occupational Health and Environmental Control, and Subpart J, Welding and Cutting.

Material Handling

On construction sites, it seems that materials, equipment, and people are constantly on the move. Materials are transferred from the laydown or staging area to where they are needed on the project. Scrap and waste materials are transported to a collection area for disposal. Workers are moving from place to place on foot or in vehicles. All of this movement creates a significant risk of accidents and injuries. The OSHA construction standards provide some important guidelines to aid in this complex choreography.

Forklifts, also called powered industrial trucks, are the workhorses of the construction industry. They significantly reduce the need for manual material handling and make bulk storage and movement of materials possible. Operating a forklift is not like driving a car or truck. Forklift operators must understand the handling and stability characteristics before they are allowed to operate on a job site. OSHA has very specific training requirements for forklifts that require operators to demonstrate their competence (OSHA, 2014). It is also important to note that the construction standards refer back to the general industry standards for all the specific forklift training requirements. The operator training requirement can be found at 29 CFR 1910.176(l).

On larger construction sites, cranes may also be used to stage and move materials. The unique hazards and risks of crane operations will be covered in Unit VI.

Not all material handling can be done with powered equipment. Workers still need to lift and carry supplies and equipment. Manual material handling is a significant source of injuries (OSHA, n.d.-b), and employees need to be trained in proper lifting technique as well as when to ask for help in lifting.

Tools

Construction tools come in many forms: non-powered hand tools such as hammers and screwdrivers; powered hand tools like drills, saws, and nail guns; and larger bench-mounted tools such as abrasive grinders and table saws. There are a number of common safety guidelines for all tools from OSHA (n.d.-d):

 maintain the tool regularly,

 use the right tool for the job,

 inspect the tool before use,

 operate according to the manufacturer’s instructions, and

 use the right PPE.

UNIT x STUDY GUIDE

Title

Old, worn, and broken hammers, chisels, and other non-powered hand tools can often be seen on construction sites. These tools get heavy use and need to be replaced at regular intervals. Electric-powered hand tools are significant sources of serious injury when they are not maintained adequately or are used incorrectly. Electric tools must either be grounded or double insulated to protect workers from electric shock (OSHA, n.d.-d). All power tools must be equipped with guards that protect workers from the point of operation, in-running nip points, rotating parts, and flying chips and sparks. Maintaining the integrity of machine guards is a significant challenge for safety professionals. Workers often feel that they can work faster or do better work if a guard is removed. It is important to get top management support for machine guarding and action taken when violations are discovered. If the organization does not take action, OSHA certainly will.

Struck-By Injuries

OSHA has identified struck-by injuries as one of the four leading causes of construction fatalities (OSHA, n.d.- a). Many of the hazards that cause struck-by injuries involve tools and material handling.

Click on the image below for an example of a common struck-by hazard.

Unit IV Construction Math Application Project

One thing that is important for safety professionals to understand is the concept of load and load capacity when lifting heavy items overhead. If you have spent any time on a construction site, this should be blatantly obvious as materials are frequently lifted via crane or other lifting devices to higher levels where the material is needed. Losing a load due to use of a sling that is not properly rated for the lift could result in a serious struck-by hazard.

In lifting an item, it is important to understand some basic physics because comparing the load rating for rigging or a sling, for instance, is not always as simple as knowing the load rating and the weight of the load. A number of factors can influence the actual load placed on a sling by the load. Consider holding a gallon of milk in your hand with your arm by your side and then raising that gallon of milk by extending your arm out to the side. A lot more strain is placed on your arm at full extension even though the weight of the milk has not changed due to the lever action placed on the body and your shoulder muscles.

Similar situations impact lifting loads with respect to how angles impact specific lifts. This is why crane operators are required to be trained in understanding how to read a load chart, which helps them to account for changes in crane capacity based on boom angle and boom length. Generally speaking, the longer the boom and the lower the angle of the lift, the lower the lifting capacity.

In this unit, our math application exercise will deal with the application of considering angles in lifting loads to provide you with a basic understanding of some of the math tools commonly applied to such situations. This will require a very basic understanding of trigonometry.

The term trigonometry might sound a bit scary, but it basically involves mathematical relationships dealing with right triangles (triangles with one 90˚ angle). Right triangles come in handy because the lengths of the triangle sides and angles within the triangles depend on each other. Consider the triangle below.

https://online.waldorf.edu/CSU_Content/Waldorf_Content/ZULU/EmergencyServices/OSH/OSH3401/W15Ec/UnitIV_LessonActivity.ppsx

UNIT x STUDY GUIDE

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You may have heard of Pythagorean’s theorem, which is basically c2 = a2 + b2. Here, c is the longest leg of the triangle (known as the hypotenuse), and knowing the length of the other two legs allows one to determine the length of c. There are other relationships as well between the angles and length of the legs of the triangle. You may have heard the terms sine, cosine, and tangent used before. These math terms are actually a lot more basic than folks might imagine. Here is how they are determined:

 sin A = a/c (The sine of angle A equals the length of leg a divided by the length of c.)

 cos A = b/c (The cosine of angle A equals the length of leg b divided by the length of c.)

 tan A = a/b (The tangent of angle A equals the lengths of leg a divided by the length of leg b.)

Another relationship that comes in handy when doing basic trigonometry is that the total of the three angles of a triangle is always 180˚.

All of this is not rocket science (although trigonometry is often used in rocket science). However, knowing just a few relationships of right triangles can help us understand math fundamentals related to issues that we might need to deal with as safety professionals. For instance, knowing we are 100 ft. from a tower on level ground and the angle from the ground to the top of the tower, we can calculate the tower’s height using these very basic relationships.

Using algebra, we can also come up with other useful relationships related to the triangle. See below:

 sin A = a/c

 a = c x sin A  c = a/sin A

Another useful application of trigonometry deals with forces. Instead of using the length of legs in a triangle, one can apply actual forces being exerted at specific angles as though the forces were actually lengths of the legs and hypotenuse of the right triangle. For instance, given our triangle above, if we are lifting a heavy, concrete pipe with a sling attached to two ends of the pipe, we can determine the actual load placed on the sling to determine if the sling is properly rated for the lift. Let’s try this out.

UNIT x STUDY GUIDE

Title

In this situation, a = one half the load because there are two legs to the sling—each one carrying half of the load—so the downward force at the midline would be halved. That is to say, the main lift line above carried the full force of the load (1,000 lbs), but at the point where the sling took over, that downward force was halved by the two legs of the sling. However, the sling itself is under much more force than just the 500 lbs even though it is carrying just half the load due to the shallow angle at A (30˚). Again, consider how heavy a gallon of milk feels when you hold your arm carrying the container out to the side. It is much easier to carry the container close to your body.

Now, applying a little algebra and replacing the variables with actual numbers, we get the result below.

Doing this on your computer’s scientific calculator is pretty simple. You should have an option to get to the scientific version of your computer’s calculator. (If you do not have a scientific calculator with trigonometric functions lying around.) Once you access the calculator, simply divide 500 by the sine of 30. To get the sine of 30, you simply enter 30 and then click on the “sin” button.

Therefore, each length of the sling is carrying a load of 1,000 lbs. However, if the sling angle were increased, the lengths of the sling would be under less of a load. You can do the math yourself if you are curious. Replace the 30˚ angle with a 45˚ angle, and see what you get. What if you try a 60˚ angle?

With this said, there are rules of thumb that can be applied based on the sling angle for this kind of problem.

In summary, the purpose of this short math lesson was to provide you with some insight as to how the angle created by the placement needs to be considered in sling selection to prevent overloading. Dropped loads can be serious struck-by hazards. You were also provided with some trigonometry basics, and hopefully you found the math to be fairly easy to do. If you plan to sit for certification exams in the future, you will need to become even more familiar with performing similar calculations.

References

Almeida, A. (n.d.). Arnaldo Almeida's safe cartoons [Image]. Retrieved from http://www.almeidacartoons.com/Safe_toons1.html

1000 sin30

500

sinA

a c 

UNIT x STUDY GUIDE

Title Asfahl, C. R., & Rieske, D. W. (2010). Industrial safety and health management (6th ed.). Upper Saddle River,

NJ: Pearson.

Occupational Safety and Health Administration. (n.d.-a). Construction focus four training. Retrieved from https://www.osha.gov/dte/outreach/construction/focus_four/index.html

Occupational Safety and Health Administration. (n.d.-b). Materials handling, storage, use, and disposal [PowerPoint slides]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Occupational Safety and Health Administration. (n.d.-c). Personal protective equipment [PowerPoint slides]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Occupational Safety and Health Administration. (n.d.-d) Tools—hand and power [PowerPoint slides]. Retrieved from https://www.osha.gov/dte/outreach/construction_generalindustry/const_outreach_tp.html

Occupational Safety and Health Administration. (2014). Construction industry digest. Retrieved from https://www.osha.gov/Publications/osha2202.pdf