NASCLA Accredited Exam: Contractor Seminar - 230 Questions and Answers, Exams of Medicine

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NASCLA ACCREDITED EXAM JJ JOHNSON

CONTRACTOR SEMINAR 230 QUESTIONS AND

ANSWERS

1. What are 4 types of Steel Decking?: Composite, Roof, Cellular, and Form
2. What are the lengths of Full sheets of Steel Decking?: 12", 18", 24", 30", or 36". All are usually less than 40"
3. Who has full responsibility for Safety on a construction site?: The prime contractor
4. Who is responsible to ensure workers have appropriate eye protection?: The employer
5. Safety belt lanyard shall be a minimum of?: 1/2 inch nylon, w/ max length to provide for a fall of no greater than 6ft. The rope shall have a nominal breaking strength of 5,400 lbs.
6. When should safety nets be provided?: When workplaces are more than 25 feet above ground or water surface or where use of ladders, scaffolds, catch platforms, temporary floors, safety lines, or safety belts are impractical
7. What are the different types of Safety Equipment?: Head, Eye and Face, and Respiratory protection. Safety belts, lifelines, lanyards, and safety nets
8. Where should quantities of flammable liquid in excess of 25 gallons be stored in that is acceptable or approved?: Acceptable wooden storage and

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Approved metal storage cabinets. Cabinets shall be labeled in conspicuous lettering "Flammable-Keep Away from Open Flames"

9. LP-Gas storage outside of buildings for containers waiting use shall be located from the nearest building or group of buildings in accordance to?: 1. 500 lbs or less - 0ft
10. ***501 to 6,000 lbs - 10ft
11. 6,001 to 10,000 lbs - 20ft
12. Over 10,000 lbs - 25ft
13. Clearance and mounting of temporary heating devices are?: 1. Room heater, circulating type - 12" sides, 12" rear, 18" chimney connector
14. ***Room heater, radiant type - 36" sides, 36" rear, 18" chimney connector
15. How far shall heaters used in the vicinity of the combustible tarpaulins, canvas, or similar coverings be located from the coverings?: 10 feet from coverings
16. Material stored inside buildings under construction shall not be placed with what distances?: 6 feet of any hoistway or inside floor openings, ***not within 10 feet of exterior wall which does not extend above the top of the material stored
17. Bagged materials shall be stacked by stepping back the layers and cross- keying the bags at least by how many bags high?: 10 bags high
18. Brick stacks shall not be more than?: 7 feet in height

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15. When a loose brick stack reaches a height of 4 feet, it shall be tapered back by how many inches?: 2 inches in every foot of height above the 4-foot level 16 When masonry blocks are stacked higher than 6 feet, the stack shall be tapered back how far?: Back one-half block per Tier above the 6-foot level
16. Used lumber shall have what withdrawn before stacking?: Nails
17. How shall lumber be stacked?: On level and solid supported sills, and stable and self supporting
18. Lumber piles shall not Exceed?: 20 feet in height provided that lumber to be handled manually shall not be stacked more than 16 feet high
19. Wire rope shall not be used if?: In any length of eight diameters, the total number of visible broken wires exceeds 10 percent of the total number of wires, or if rope shows other signs of excessive wear, corrosion, or defect
20. Waste materials - when materials are dropped more than 20 feet to any point lying outside the exterior walls of the building what is needed?: An enclosed chute of wood, or equivalent material, shall be used. Enclosed chute is a slide, closed in on all sides, through which material is moved from a high place to a lower one
21. All other hand-held powered tools such as circular saws, chain saws, and percussion tools without positive accessory holding means, shall be equipped with what?: A constant pressure switch that will shut off the power when the pressure is released
22. Compressed air shall not be used for cleaning purposes except when?: Where reduced to less than 30 p.s.i and then only with effective chip guarding and

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personal protective equipment which meets the requirements. The 30 psi requirement does not apply for concrete form, mill scale and similar cleaning purposes 24. Who shall be allowed to operated a powder-actuated tool?: Only employees who have been trained in the operation of the particular tool in used

25. All employees using abrasive wheels shall be protected by?: Eye protection equipment
26. Guarding, all portable, power-driven circular saws shall be equipped with what?: Guards above and below the base plate or shoe. The upper guard shall cover the saw to the depth of the teeth, except for the minimum arc required to permit the base to be tilted for bevel cuts. The lower guard shall cover the saw to the depth of the teeth, except for the minimum arc required to allow proper retraction and contract with the work. When the tool is withdrawn from the work, the lower guard shall automatically and instantly return to the covering position.
27. Valve protection caps shall not be used for lifting cylinders from one vertical position to another.: Bars shall not be used under valves or valve protection caps to pry cylinders loose when frozen. Warm, not boiling, water shall be used to thaw cylinder loose 28 How should compressed air be secured?: In an upright position at all times except, if necessary, for short periods of time while cylinders are actually being hoisted or carried
28. What distance shall Oxygen cylinders in storage be separated from fuel-gas cylinders or combustible materials (especially oil or grease)?: A minimum

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distance of 20 ft (6.1m) or by non-combustible barrier at least 5 ft (1.5m) high having fire-resistance rating of a least one-half hour.

30. Inside of buildings, how shall Gas cylinders be stored?: In a well protected, well-ventilated, dry location, at least 2 ft (6.1m) from highly combustible materials such as oil or excelsior. Cylinders should be stored in definitely assigned places away from elevators, stairs, or gangways. Assigned storage places shall be located where cylinders will not be knocked over or damaged by passing or falling objects, or subject to tampering by unauthorized persons. Cylinders shall not be kept in unventilated enclosures such as lockers and cupboards.
31. How shall a regulator to a cylinder valve be connected?: The valve shall be opened slightly and closed immediately. (The action is generally termed "cracking" and is intended to clear the valve of dust or dirt that might otherwise enter the regulator.) The person cracking the valve shall stand to one side of the outlet, not in front of it. The valve of fuel gas cylinder shall not be cracked where the gas would reach welding work, sparks, flame, or other possible sources of ignition.
32. All hose in use, carrying acetylene, oxygen, natural or manufactured fuel gas, or any gas or substance which may ignite or enter into combustion, or be in any way harmful to employees shall?: Be inspected at the beginning of each working shift. Defective hose shall be removed from service.
33. When the arc welder or cutter has occasion to leave his work or to stop work for any appreciable length of time, or when the arc welding or cutting machine is to be moved, what should happen?: The power supply switch to the equipment shall be opened.

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34. Lifelines. Where a welder must enter a confined space through a manhole or other small opening, what should occur?: Means shall be provided for quickly removing him in case of emergency. When safety belts and lifelines are used for this purpose they shall be so attached to the welder's body that his body cannot be jammed in a small exit opening. An attendant with a pre-planned rescue procedure shall be stationed outside to observe the welder at all times and be capable of putting rescue operations into effect.
35. Working Clearances (voltage): 1. Nominal voltage to ground, 0 - 150 = Minimum clear distance for conditions are 3 ft, 3ft, 3ft
36. Nominal voltage to ground, 151-600 = Minimum clear distance for conditions are 3ft, 3.5ft, 4ft 36 Minimum Depth of Clear Working Space in Front of Electrical Equipment: 1. Nominal voltage to ground, 601 to 2,500 = Conditions 3ft, 4ft, 5ft
37. Nominal voltage to ground, 2,501 to 9,000 = Conditions 4ft, 5ft, 6ft
38. Nominal voltage to ground, 9,001 to 25,000 = Conditions 5ft, 6ft, 9ft
39. Nominal voltage to ground, 25,001 to 75kV = Conditions 6ft, 8ft, 10ft
40. Nominal voltage to ground, Above 75kV = Conditions 8ft, 10ft, 12ft
41. Each scaffold and scaffold component shall be capable of support, without failure, what?: Its own weight and at least 4 times the maximum intended load applied or transmitted too it
42. Each scaffold unit shall be installed so that the space between adjacent units and the space between the platform and the uprights is?: No more than 1 inc

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(2.5cm) wide, except where the employer can demonstrate that a wider space is necessary (for example, to fit around uprights when side brackets are used to extend the width of the platform)

39. Each scaffold platform and walkway shall be?: At least 18 inches (46cm) side
40. The front edge of the platforms shall: Not be more than 14 inches (36cm) from the face of the work, unless guardrail systems are erected along the front edge and/or personal fall arrest systems are used in accordance with paragraph G
41. The maximum distance from the face for outrigger scaffolds shall be?: 3 inches (8cm)
42. The maximum distance from the face for plastering and lathing operations shall be?: 18 inches (46cm)
43. Each end of a platform, unless cleated or otherwise restrained by hooks or equivalent means, shall?: Extend over the centerline of its support at least 6 inches (15 cm)
44. Each end of a platform 10 feet or less in length shall?: Not extend over its support more than 12 inches (30 cm) unless the platform is designed and installed so that the cantilevered portion of the platform is able to support employees and/or materials without tipping, or has guardrails which block employee access to the cantilevered end
45. On scaffolds where platforms are overlapped to create a long platform, the overlap shall?: Ocurr only over supports, and shall not be less than 12 inches (30 cm) unless the platforms are nailed together or otherwise restrained to prevent movement

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46. Scaffold components manufactured by different manufacturers shall not be?: Intermixed unless components fit together without force and structural integrity is maintained by the user. Components shall not be modified in order to intermix them unless a competent person determines the resulting scaffold is structurally sound. 47 Supported scaffold poles, legs, posts, frames, and upgrights shall?: Bear on base plates and mud sills or other adequate firm foundation. Footings shall be level. Unstable objects shall not be used. Front-end loaders and similar equipment shall not be used for support unless they are specifically designed by the manufacturer. Fork-lifts shall not be sued.
    48. Fall protection: Each employee on a scaffold more than 10 feet (3.1m) above a lower level shall be protected from falling to that lower level.: Each employee on a boatswains' chair, catenary scaffold, float scaffold, needle beam scaffold, or ladder jack scaffold shall be protected by a personal fall arrest system. Each employee on a single-point or two-point adjustable suspension scaffold shall be projected by both personal fall arrest system and guardrail system. Each employ on a crawling board (chicken ladder) shall be protected, a guardrail system (200lb minimum) or by 3/4" diameter grabline or equivalent handhold securely fastened beside each crawling board. Each employee on a self-contained adjustable scaffold shall be protected by a guardrail system (200lb min). Each employ on a walkway located within a scaffold shall be protected by a guardrail system (200lb min) installed within 9.5 in of and along at least one side of the walkway. Each employee performing overhand bricklaying operations from a supported scaffold

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shall be protected from falling from all open sides and ends of the scaffold (except at the side next to the wall being laid) by the use of a personal fall arrest system or guardrail system (200 lbs min).

49. The top edge height of toprails or equivalent member on support scaffolds manufactured or placed in service after January 1, 2000 shall be?: Installed between 38 inches (.97m) and 45 inches (1.2m) above the platform surface. The top edge height on supported scaffolds manufactured and placed in service before Jan 1, 2000 and on all suspended scaffolds where both guardrail and a personal fall arrest system are required shall be between 36 inches and 45 inches. When conditions warrant, the height of the top edge may exceed the 45 inch height, provided the guardrail system meets all other criteria.
50. Scaffold casters and wheels shall be?: Locked with positive wheel and/or wheel and swivel locks, or equivalent means, to prevent movement of the scaffold while the scaffold is used on stationary manner.
51. Each employee who is constructing a leading edge 6 feet or more above lower levels shall be protected from falling by a guardrail systems, safety net systems, or personal fall arrest systems.: Exception: When the employer can demonstrate that it is infeasible or creates a grater hazard to use these systems, the employer shall develop and implement a fall protection plan which meets the requirements. 52 Each employee reaching more than 10 inches below the level of walking/working surface on which they are working, shall: Be protected from falling by a guardrail system, safety net system, or personal fall arrest system.

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53. Wall openings: Each employee working on , at, above, or near wall openings (including those with chutes attached) where the outside bottom edge of the wall opening is 6 feet or more above lower levels and the inside bottom edge of the wall opening is less than 39 inches above the walking/working surface, shall be protected from falling by used of a guardrail system, a safety net system, or a personal fall arrest system
54. To edge height of top rails, or equivalent guardrail system members, shall: Be 42 inches plus or minus 3 inches above the walking/working level. When conditions warrant, the height of the top edge may exceed the 45 inch height, provided the guardrail system meets all other criteria of this paragraph.
55. Intermediate members (such as balusters), when used between posts, shall: Be not more than 19 inches apart
56. Top rails and midrails shall: Be at least one-quarter inch nominal diameter or thickness to prevent cuts and lacerations. If wire rope is used for top rails, it shall be flagged at not more than 6 foot intervals with high-visibility material
57. Safety nets and safety net installations shall: Be drop-tested at the jobsite after initial installation and before being used as a fall protection system, whenever relocated, after major repair, and at 6 month intervals if left in one place. The drop-test shall consist of a 400 pound bag of sand 30 +/- 2 inches in diameter dropped into the net from the highest walking/working surface at which employees are exposed to fall hazards, but not from less than 42 inches above that level 58. Horizontal lifelines shall be designed, installed, and used,

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under the supervision of a qualified person: as part of a complete personal fall arrest system, which maintains a safety factor of a least two

59. The attachment point of the body belt shall: Be located in the center of the wearer's back. The attachment point of the body harness shall be located in the center of the wearer's back near shoulder level, or above the wearer's head.
60. When mechanical equipment is not being used,: The warning line shall be erected not less than 6 feet from the roof edge
61. After being erected, with eh rope, wire, or chain attached, stanchions shall: Be capable of resisting, without tipping over, a force of at least 16 pounds applied horizontally against the stanchion, 30 inches above the walking/working surface, perpendicular to the warning line, and in the direction of the floor, roof, or platform edge
62. Covers for holes in floors, roofs, and other walking/working surfaces shall: Meet the following requirements:

1. Covers located in roadways and vehicular aisles shall be capable of supporting, without failure, at least twice the maximum axle load of the largest vehicle expected to cross over the cover
2. All other covers shall be capable of supporting, without failure, at least twice the weight of employees, equipment, and materials that may be imposed on the cover at any one time.
3. All covers shall be secured when installed so as to prevent accidental displacement by the wind, equipment, or employees.
4. All covers shall be color coded or they shall be marked with the word "HOLE" or "COVER" to provide warning of the hazard.
5. During the performance of roofing work: 1. Materials and equipment shall not be stored within 6 feet of a roof edge unless guardrails are erected at the edge
6. Materials which are piled, grouped, or stacked near a roof edge shall be stable and self-supporting.
7. Certification of training: The employer shall verify compliance by preparing a written certification record. The written certification record shall contain the name or other identity of the employee trained, the date of the training, and the signature of the employer: If the employer relies on training conducted by another employer or completed prior to the effective date of the section, the certification record shall indicate the date the employer determined the prior training was adequate rather than the date of actual training
8. Shield system: Means a structure that is able to withstand the forces imposed on it by a cave-in and thereby protect employees within the structure. Shields can

be permanent structures or can be designed to be portable and moved along as work progresses. Additionally, shields can be either premanufactured or job-built in accordance with 1926.652. Shields used in trenches are usually referred to as "trench boxes" or "trench shields".

66. Means of egress from trench excavations. A stairway, ladder, ramp or other sae means of egress shall?: Be located in trench excavations that are 4 feet or more in depth so as to require no more than 25 feet of lateral travel for employees.
67. Where oxygen deficiency (atmospheres containing less than 19.5 percent oxygen) or a hazardous atmosphere exists or could reasonably be expected to exist, such as excavations in landfill areas or excavations in areas where hazardous substances are stored nearby, the atmospheres in the excavation shall?: Be tested before employees enter excavations greater than 4 feet in depth.
68. Employees shall be protected from excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations.: Protections shall be provided by placing and keeping such materials or equipment at least 2 feet from the edge of excavations, or by the use of retaining devices that are sufficient to prevent materials or equipment from falling or rolling into excavations, or by a combination of both if necessary.
69. Each employee in an excavation shall be protected from cave-ins by an adequate protective system designed in accordance with this section except when?: Excavations are less than 5 feet in depth and examination of the ground by competent person provides no indication of a potential cave-in

70. Additional requirement for shield systems used in trench excavations. Excavations of earth material to a level not grater than 2 feet below the bottom of a shield shall?: Be permitted, but only if the shield is designed to resist the forces calculated for the full depth of the trench, and there are no indications while the trench is open of a possible loss of soil from behind or below the bottom of the shield.
71. Manual tests. Manual analysis of soil samples is conducted to determine quantitative as well as qualitative properties of soil and to provide more information in order to classify soil property: 1. Plasticity. Mold a moist or wet sample of soil into a ball and attempt to roll it into threads as thin as 1/8 inch in diameter. Cohesive material can be successfully rolled into threads without crumbling. For example, if a least a two inch length of 1/8 inch thread can be held on one end with-out tearing, the soil is cohesive.
72. Thumb penetration test can be used to estimate the unconfined compressive strength of cohesive soils. Type A soils with an unconfined compressive strength of 1.5 tsf can b readily indented by the thumb, however, they can be penetrated by the thumb only with very great effort. Type C soils with an unconfined compressive strength of .5 tsf an be easily penetrated several inches by the thumb, and can be molded by light finger pressure. The test should be conducted on an undisturbed soil sample, such as a large clump of spoil, as soon as practicable after excavation to keep to a minimum the effects of exposure to drying influences. If the excavation is later exposed to wetting influences (rain, flooding), the classification of the soil must be changed accordingly.

3. Dry Strength. If soil is dry and crumbles on its own or with moderate pressure into individual grains or fine powder, it is granular (gravel, sand, or silt). If the soil is dry and falls into clumps which break u into smaller clumps, but the smaller clumps can only be broken u with difficulty, it may be clay in any combination with gravel sand or silt. If the dry soils breaks into clumps which do not break up into small clumps and which can only be broken with difficulty and there is no visual indication the soil is fissured the soil may be considered unfissured.
4. Type A means cohesive soils with an unconfined compressive strength of 1. ton per square foot (tsf) or greater. Examples of cohesive soils are: clay, silty clay, sandy clay, clay loam and, in some cases silty clay loam and sandy clay loam. Cemented soils such as caliche and hardpan are also considered Type A.: However, no soil is Type A if:
5. The soil is fissured or
6. The soil is subject to vibration from heavy traffic, pile driving, or similar effects or
7. The soil has been previously disturbed or
8. The soil is part of a sloped, layered system where the layers dip into the excavation on a slope of four horziontal to one vertical (4H:1V) or greater, or
9. The material is subject to other factors that would require it to be classified as a less stable material.
10. Excavations made with Type A soil, Figure B-1: 1. All simple slope excavations 20 feet or less in depth shall have a maximum allowable slope of 3/4:1. Exception,

simple slope excavations which are open 24 hours or less (short term) and which are 12 feet or less in depth shall have a maximum allowable slope of 1/2:1 2. All simple benched excavations 20 feet or less in depth shall have a maximum allowable slope of 3/4:1 and maximum bench dimensions as follows.

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20' --4'max-- -------

3. All excavations 8 feet or less in depth which have unsupported vertically sidded lower portions shall have a maximum vertical side of 3-1/2 feet. The slope is still 3/4:
4. Cast-in-place concrete. General requirements for formwork: 1. FORM- WORK shall be designed, fabricated, erected, supported, braced and maintained so that it will be capable of supporting without failure all vertical and lateral loads that may reasonably be anticipated to be applied to the formwork. Forwork which is designed, fabricated, erected, supported, braced and maintained in conformance with the Appendix to this section will be deemed to meet the requirements of this paragraph.
5. Drawings or plans, including all revisions, for the jack layout formwork (including shoring equipment), working decks, and scaffolds, shall be available at the jobsite.
   75. All masonry walls over 8 feet in height shall: Be adequately braced to prevent overturning and to prevent collapse unless the wall is adequately supported so that

it will not overturn or collapse. The bracing shall remain in place until permanent supporting elements of the structure are in place.

76. Working under loads. Routes for suspended loads shall be pre-planned to ensure that no employee is required to work directly below a suspended load except for:: 1. Employees engaged in the initial connection of the steel, or
77. EMPLOYEES necessary for the hooking or unhooking of the load
78. The following additional requirements shall apply for multiple story structures: 1. THE permanent floors shall be installed as the erection of structural members progresses, and there shall be not more than eight stores between the erection floor and the upper-most permanent floor, except where the structural integrity is maintained as a result of the design
79. AT NO time shall there be more than four floors or 48 feet, whichever is less, of unfinished bolting or welding above the foundation or uppermost permanently secured floor, except where the structural integrity is maintained as a result of the design.
80. A FULLY planked or decked floor or nets shall be maintained within two stories or 30 feet whichever is less, directly under any erection work being performed.
81. Landing and placing loads: The weight of a bundle of joist bridging shall not exceed a total of 1,000 pounds. A bundle of joist bridging shall be placed on a minimum of three steel joists that are secured at one end. The edge of the bridging bundle shall be positioned with 1 foot of the secured end.

79. Demolition: When debris is dropped through the holes in the floor without the use of chutes, the area onto which the material is dropped shall?: Be completely enclosed with barricades not less than 42 inches high and not less than 6 feet back from the projected edge of the opening above. Signs, warning of the hazard of falling materials, shall be posted at each level. Removal shall not be permitted in this lower aread until debris handling ceases above.
80. Chutes:: No material shall be dropped to any point lying outside the exterior walls of the structure unless the area is effectively protected.
81. Access and Egress:: 1. Employer shall provide and maintain safe means of access and egress to all work stations
82. Employer shall provide access and egress in such a manner that employees are protected from being struck by excavators, haulage machines, trains and other mobile equipment
83. Employer shall control access to all openings to prevent unauthorized entry underground. Unused chutes, manways, or other openings shall be tightly covered, bulkheaded, or fenced off, and shall be posted with warning signs indicating "Keep Out" or similar language. Completed or unused sections of the underground facility shall be barricaded.
84. Ladders and Job-made ladders: Each portable ladder that is not self- supporting. At least four times the maximum intended load, except that each extr-heavy-duty type 1A metal or plastic ladders shall sustain at least 3.3 times the maximum intended load. The ability of a ladder to sustain the loads indicated shall be placed at an angle of 75 1/2 degrees from the horizontal.

83. When portable ladders are used for access to an upper landing surface, the ladder side rails shall: Extend at least 3 feet above the upper landing surface to which the ladder is used to gain access; or, when such an extension is not possible because of the ladder's length, then the ladder stall be secured at its top to a rigid support that will not deflect, and a grasping device, such as a grabrail, shall be provided to assist employees in mounting and dismounting the ladder. In no case shall the the extension be such that the ladder deflection under a load would, by itself, cause the ladder to slip off its support.
84. Non-self-supporting ladders: Shall be used at an angle such that the horizontal distance from the top support to the foot of the ladder is approximately one- quarter of the working length of the ladder (distance along the ladder between the foot and the top support)
85. The top or top step of a stepladder shall: NOT be used as a step
86. When ascending or descending a ladder: The user shall face the ladder 87. Devices originally designed by the manufacturer for use as: A safety device, operational aid, or a means to prevent power line contact or electrocution, when used to comply must meet the manufacturer's procedures for use and conditions or use: Minimum Clearance Distance:: 1. UP TO 50 kv - > 10 FEET MIN clearance
87. over 50 to 200 kv - > 15 feet min clearance
88. Over 200 to 350 kv - > 20 feet min clearance
89. A competent person must begin a visual inspection prior to each shift the equipment will be used, which must be completed before or during that shift.:

The inspection must consist of observation for apparent deficiencies. Taking apart equipment components and booming down is not required as part of this inspection unless the results of the visual inspection or trial operation indicate that further investigation necessitating taking apart equipment component or booming down is needed. Determinations made in conducting the inspection must be reassessed in light of observations made during operation. At minimum the inspection must include all of the following:

1. Control mechanisms for maladjustments
2. Control and drive mechanisms
3. Air, hydraulic, and other pressurized lines
4. Hydraulic system for proper fluid level
5. Hooks and latches for deformation
6. Wire, rope reeving for compliance
7. Wire rope
8. Electrical apparatus
9. Tires
10. Ground conditions around the equipment for proper support
11. The equipment for level position
12. Operator cab windows
13. Rails, rail stops, rail clamps and support surfaces
14. Safety devices and operational aids

89. Scaffolds shall be erected, moved, dismantled, or altered only under the supervision and direction of a?: Competent person quilified in scaffold erection, moving, dismantling or alteration. Such activities shall be performed only by experienced and trained employees selected for such work by the competent person 90. Before an employee enters the space, the internal atmosphere must be tested, with a calibrated direct-reading instrument, for oxygen content, for flammable gases and vapors, and for potential toxic air contaminants, in that order.: Any employee who enters the space, or that employee's authorized representative, must be provided an opportunity to observe the pre-entry testing required
    91. Oxygen Level: Minimum oxygen content of 19.5%
    92. Excavation: To find the load factor for common swell percentage: Divide the bank volume by the bank volume plus the swell percentage: For example, a soil that swells by 25% has a load factor of 0.80 (1 LCY / 1.25 LCY)
    93. Bank Cubic Yards (BCY) - undisturbed Loose Cubic Yards (LCY) - disturbed (swells) Compacted Cubic Yards (CCY) - compacted (shrinks): 1. LCY = 1 BCY x 1.32 Example if truck capacity is 14 LCY and you need to export 1,000 BCY. Convert BCY to LCY, 1000 BCY x 1.32 = 1,320 LCY. Now take 1,320 LCY / 14 LCY = 95 haul trips 2. CCY = 1 LCY / 1.54 Example: 1,320 / 1.54 = 857 CCY
90. CUT = 4,000BCY x 1.32 LCY/BCY = 5,280LCY FILL = 4,000CCY x 1.54 LCY/CCY = 6,160 LCY

6,160LCY-5,280LCY = 880LCY more needed

94. Trench volume: Example: trench is 100ft long by 2ft wide by 5ft deep. 100x2x5 = 1,000 BCF BCY = 1000BCF / 27 = 37BCY
95. Bulldozers: Each size and type of dozer has a range of appropriate uses and applications. Light utility rand from 40 to 80 hp and have blade capacity of 1.25 to 2.25 CY. Typical applications include residential and commercial foundations, grading, backfill, landscaping, light logging, and swamp dozing. 96. Load time: Load time can be reduced by loading downgrade
96. Using pusher assistance will increase the loading rate: Pushers should be powerful and heavy enough to push the scrapers through the cut ad accelerate, or boost, the scrapers as they leave the cut
97. Reading plans - common plan symbols for underground utility work: Refer to Google Drive - JJJohnson Folder 3 pictures
98. Reference stake information: One station equals 100 feet. Example: Actual elevation at TOS is 1527.25 ft but express as 100ft, then another at 1524.5 ft would be expressed as 1527.25-1524.5=2.75. 100 - 2.75 = 97.25ft
99. Slopes expressed in percents and degrees: An easy way to remember how to calculate slope in percentage terms. A 45-degree slope is 100-percent slope. If the vertical rise is equal to the horizontal distance, the slope is 100%.

To calculate the slope as percent, divide the vertical rise by the horizontal distance, then multiple by 100. 83ft rise / 227 ft dist *100 = 36.5%

101. Best equipment to excavate loose soil: For trenches deeper than 8 ft, or extremely hard digging, the track backhoe should be your first choice. Used wisely, a track backhoe can increase your production rate and your profits
102. Shoring Jacks: Shoring jacks are the best choice when working in firm soil that will stay in place long enough for the jacks to be positioned. Can be placed and removed without entering the trench
103. Proctor Tests: The standard Proctor test was developed in early 1930s by RR Proctor, a field engineer for the City of Los Angeles. Applying heavy weight to a completely dry soil sample won't acieve much increase in density. When water is added it's much easier to increase the density. Water acts as a lubricant. The standard Proctor test is usually specified for fill material designated for use under building slabs and sidewalks, and in utility trenches under grassy areas. A sampl of the proposed fill material is crushed so it can pass thru a 3/4inch sieve. A steel cylinder mold is filled with the sample in 3 layers. Each layer is struck 25 times with a 5.5lb, 2inch diameter hammer before the next layer is added.
104. Soil Density Test: The most convenient, accurate and relatively inexpensive method of determining in-place soil density and moisture content is to use a Nuclear Density Gauge (nuclear meter, ASTM 2922).
105. Compression Strength:

106. Contour Lines: Before you can estimate cut and fill quantities, you need to be familiar with topographic (contour) maps and contour lines. Contour lines on the map represent the third dimension (relief) of the ground surface. Contour lines represents points of equal elevation above or below an arbitrary reference (datum) plan such as sea level or top-of-slab (TOS) elevation.
107. Single Charge Blasting: There are 2 common blasting techniques: single charge and sequential fireing. Single charge is the simplest form of blasting. The powder-man drills a hole in the rock, places and explosive charge in the hole and sets it off. The shock wave of the explosion travels in the directrion of least resistance - up, sideways or, in rare cases, down.
108. To find the load factor, divide the bank volume by the back volume plus the swell percentage: For example: a soil that swells by 25% has a load factor of .80 (1 LCY / 1.25 LCY)
109. Slot dozing: Is one technique that can reduce the amount of load lost in transit. When slot dozing, the dozer works within a roughly 2 foot trench that's the same width as the blade. Pushing the soil in the slot keeps the load from slipping away. 110. Well point system better in course grained soil: If you have a lot of pipe to install in bad groundwater conditions, consider dewatering ahead of pipe laying. Wellpoints, placed around the excavation site, are a potent dewatering solution. A wellpoint is a perforated tube that brings water to the surface via a suction tube (riser pipe). 20ft suction lift. pump 10-25 gallons per minute

111. In post-tensioned concrete, until the concrete hardens to about 75% of it's full strength,: The tendon is not pulled (stressed). Therefore, initially both concrete and tendon have no stress. Needs to harden to 75% compression strength before jacking.
112. When a member is designed so that under the working load there are no tensile stresses in it, then the concrete is said to be fully prestressed. On the other hand, if tensile stresses are allowed to be produced in the member under working load, then it is termed partially prestressed (the process of applying a percentage of the final force at some earilier time than the normal 72 hours): For partial prestressing additional mild steel rebar may be required to control cracking under tension. For economic reasons, partial prestressing is most common for of prestressing used in structures. Sufficient prestressing steel is used to offset most of the member self-weight and other sustained dead loads. Occasionally a small portion of live load is also included. The tension produced by the remainder of live load is resisted by the combination of stressed and non- stressed steel, resulting in economical structures. THE BONDED STEEL REBAR assures control of the crack width and distribution, should secondary effects or overloading cause the member to crack.
113. Unbonded tendon fabrication procedures conform to the requirements of the Post-Tensioning Institute's "Specification for Unbonded Single Strand Tendons" published July, 1993: The first step in the manufacturing process is the coating of the strand. The is accomplished using the plastic extrusion method. The bare strand is coated with P/T coating and then covered with plastic sheathing.