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Want to find the 2011 Class C Safety Officer Examination Questions

Safety Officer C Certificate Examination Questions

Single Choice Questions:

1. When excavation in wetland areas, if it is artificial precipitation, it will drop to the bottom of the pit (0.5 —1.0 meters) before excavation can be carried out.

2. When excavating in an area of ??expansive soil, (drainage work) must be done before excavation.

3. When using reinforced concrete cast-in-place piles, the excavation standard is that the concrete in the pile body reaches (after the design strength).

4. When manually excavating earth, the operating distance between two people should be maintained (1 meter).

5. The head of the shield machine should detect the concentration of combustible gas every day to achieve prediction, prevention and sequence control, and do a good job (recording the account).

6. Drainage ditches and water collection wells around the foundation pit (trough) should be set up (outside the foundation range).

7. The correction jack in the tool tube should be well insulated, and the electric high-pressure oil pump should be operated (wear insulating gloves).

8. The excavated vehicle should be guided by a commanding officer, and (overloading) is strictly prohibited.

9. When the pipe jacking method exceeds (50 meters), measures should be taken to prevent hypoxia and suffocation.

10. During pipe jacking construction. Oxygen and acetylene bottles (which are not allowed to enter the pit) are placed in the pit.

11. Lighting and telecommunications systems in pipelines generally use (low-voltage electricity).

12. The installation of supports must be carried out in the order of (slotted supports first supported and then dug).

13. The dismantling of supports should be carried out in the order of (replace the supports now and then remove them).

14. The number of reference points for foundation pit detection should not be less than (2).

15. During the installation process, the formwork and its brackets must be installed (temporary fixed facilities that can effectively prevent overturning).

16. The minimum height of the operating platform required for formwork installation operations is (2.0 meters).

17. When the fastener-type steel pipe support is higher than (4.0 meters), horizontal scissor braces are installed.

18. When working in suspended areas, operators should (fasten their seat belts).

19. The minimum distance when stacking formwork above the foundation pit (trough) should be (2.0 meters) away.

20. The angle between the diagonal support and the side formwork should not be less than (45°)

21. When the end of the wire rope is fixed with a rope clamp, the number of rope clamps should not be less than (3) .

22. Before the wire rope is broken, there are usually signs (broken wires, broken strands) and other signs, which are easy to check and prevent accidents.

23. Bending fatigue caused by multiple bends is one of the main causes of damage to steel wire ropes.

24. If the diameter of the lifting chain of the hand chain hoist exceeds (10%) wear, it should be scrapped and replaced in advance.

25. The lifting mast is a column type and is taut on the ground with ropes (cable ropes). Tighten one end to the top of the lifting mast and the other end to the ground anchor. The number of cables is generally no less than (4).

26. When lifting equipment, the number of remaining turns of the wire rope on the electric winch drum should be no less than (3) turns.

27. In lifting operations, except for the (moving pulley), ground anchors can be used to fix it.

28. The angle between the ground anchor pulling rope and the horizontal is generally less than (30°).

29. The diameter of the pulley used should usually not be less than (16) times the diameter of the wire rope.

30. More than 70% of truck-type crane rollover accidents are caused by (overloading or outrigger collapse). Therefore, special attention should be paid when using truck cranes.

31. The outriggers of the truck crane must be solid. Before lifting heavy objects, the outriggers should be carefully observed to see if there is any collapse. Sometimes, in order to ensure safe use, additional pads will be added. purpose (increase the pressure-bearing area).

32. In lifting operations, it is prohibited to cable-stay or lift heavy objects buried underground or solidified on the ground.

33. When signing a construction contract with the construction unit of a demolition project, they should sign a (safety production management) agreement to clarify the safety management responsibilities of both parties.

34. Scaffolding and safety nets used in demolition construction must be erected by (professionals) and can only be used after being accepted by relevant personnel.

35. Three-dimensional (crossing) operations are strictly prohibited during demolition construction. When working horizontally, there is a certain safety distance between various types of work.

36. After the excavator operation is completed, it should be parked on a (solid, flat area).

37. When the excavator is operating with dragline or backhoe. The distance between the crawler tracks and the edge of the working surface should be greater than (1 meter),

38. When two or more excavators are operating in the same area, the front-to-back distance should be greater than 8 meters, and the left-right distance should be greater than (1.5 meters)< /p>

39. Do not use bulldozers to push (lime).

40. When two scrapers operate in parallel, the distance between them shall not be less than (2 meters)

41. The installation site of the pile driver should be flat and solid. When the specified compressive stress is reached, subgrade boxes or 30mm thick steel plates should be laid under the crawler tracks, and the spacing should not be greater than (100)mm.

42. When the pile driver is working, non-staff members should leave the machine. (10 meters) away, no one is allowed to stand under the lifting arm of the crane.

43. During the trial driving process of the pile hammer, the operator must monitor the pile hammer away from the center (5 meters).

44. Plug-in vibrators should be transported (cut off the power supply).

45. When moving the welding machine, the (power supply) should be cut off.

46. Which of the following statements about the main function of the gravitational moment limiter is correct. (To prevent overloading of the tower crane.)

47. The disassembly and assembly operations of the tower crane must be carried out (during the day).

48. (Torque limiter) can prevent the tower crane from overloading and avoid serious accidents such as overturning or arm folding of the tower crane due to severe overloading.

49. When the tower crane is working, the wind speed should be lower than level (6).

50. Which of the following safety devices is used to prevent the running car from exceeding the two extreme positions of the maximum or minimum amplitude? (Amplitude limiter)

51. The anemometer should be installed from the top of the crane to the spreader (the highest position that is not blocked from the wind)

52. (Wire rope anti-slip groove Device) can prevent the wire rope from breaking away from the pulley groove during the transmission process, causing the wire rope to get stuck or damaged.

53. (Hook safety) is a safety device that prevents the lifting wire rope from decoupling due to excessive angle or improper hook.

54. Tower crane jacking operations are not allowed when the wind force is above level 4.

55. During the tower crane lifting operation, the (crane arm) and the balance arm must be in a balanced state.

56. The fixed interval between inner climbing tower cranes shall not be less than (3) floors.

57. The clear height inside the construction elevator cage shall not be less than (2 meters).

58. The construction lift (base frame) is connected to the foundation.

59. The wall frame attached to the material hoist can be connected to the frame body and building using (steel pipe).

60. Which of the following descriptions of the use of material hoists is correct (only materials are allowed to be transported, and people are not allowed to move up and down).

61. The foundation of the material hoist is poured with c20 concrete, and the thickness shall not be less than (300㎜).

62. After the lifting wire rope is released to the maximum working length, the wire rope on the drum At least keep (3 turns).

63. When operating multiple towers, the vertical distance between the high-position tower crane (the hook is raised to the highest point) and the low-position tower crane shall not be less than (1.5 meters) under any circumstances.

64. Drainage ditches are not allowed to be dug within the perimeter (5 meters) of the material hoist foundation.

65. In which of the following situations occurs, the hook should be scrapped (the wear of the section at the lanyard exceeds 10% of the original height).

66. A horizontal horizontal rod (small horizontal rod) must be set up at the main node of the scaffolding, fastened with right-angle fasteners, and disassembly is strictly prohibited, just because (the horizontal horizontal rod bears vertical load It is an important stress-bearing member and an indispensable rod to ensure the overall stiffness of the scaffold).

67. The requirements for laying scaffolding boards on the working level of scaffolding are as follows (they should be fully paved, firmly laid, and no more than 120-150mm away from the wall).

68. The distance between the bottom layer of the scaffolding Should not be larger than (2 meters).

69. The structure of double-row scaffolding wall parts with a height of more than 24 meters is stipulated as follows (rigid wall parts must be used to reliably connect to the building).

70. The width of the scissor brace (should not be less than 4 spans, and should not be less than 6 meters).

71. The inclination angle between the scissor brace and the ground should be (between 45-60°).

72. The width and slope of transport lanes and ramps are specified (should not be less than 1.5 meters and should be 1:6).

73. The distance between the end of the horizontal horizontal pole of the double-row scaffolding against the wall and the decorative surface of the wall should not be greater than 100mm.

74. When there are equipment foundations and pipe trenches under the scaffolding foundation (if no measures are taken, they should not be excavated).

75. When erecting scaffolding, the following should be followed: (the height of one erection should not exceed two adjacent wall parts).

76. Scaffolding must be dismantled (it must be carried out layer by layer from top to bottom, and it is strictly prohibited to work up and down at the same time).

77. When the scaffolding is dismantled in sections, the scaffolding that is not dismantled (wall fittings and transverse diagonal bracing devices should be installed at both ends as required).

78. The standards for the number and quality of fastener tightening sampling inspections are as follows: (for fasteners connecting transverse horizontal rods and longitudinal horizontal rods, 5 should be sampled for every 51-91 fasteners, and irregularities are not allowed. qualified).

79. The mesh density of the fully enclosed vertical mesh used on the outside of the external scaffolding of the construction project should not be less than (2000/100㎝2).

80. Removal of steel formwork components Finally, the distance between the temporary storage place and the edge of the floor should not be less than (1 meter).

81. For cross operations on levels exceeding 24 meters in height, double-layer safety shelters should be installed at all passages where personnel enter.

82. Before carrying out high-altitude construction work, safety protection facilities should be inspected (item-by-item inspection).

83. The supporting points and upper tie points of the cantilevered steel platform must be located on the (building).

84. The acceptance of safety protection facilities should include construction organization and design and relevant verification data, as well as acceptance records of safety protection facilities. Safety protection facilities (change records and visas) and other information.

85. When working at heights in rainy or snowy days, reliable anti-slip, cold-proof and (anti-freezing) measures must be taken.

86. For roofs with a slope greater than 1:2.2, protective railings should be set (1.5 meters) high.

87. The overall structure of the fixation of the railing posts and the connection of the crossbars should enable the protective railings to withstand external forces (1000N) in any direction at any point on the upper rails.

88. The protective railing must be closed with a safety net from top to bottom, or a tightly fixed foot guard with a height of not less than (18cm) or a foot guard of 40cm must be installed under the guardrail.

89. Protective railings or fixed gates must be installed at the entrance of the elevator shaft; a safety net must be installed every two floors or at most (10 meters) in the elevator shaft.

90. Any opening with a side length exceeding (150cm) shall be surrounded by protective railings and a safety net shall be stretched under the opening.

91. For vertical openings in walls and other places, fixed protective doors should be installed on all openings that are grounded, and the distance between door grids should not be greater than (15cm).

92. If the side drop from the lower edge to the floor or window sill is less than 80 cm, or other vertical openings, a temporary guardrail (1.2 meters) high should be installed if the side drop is greater than 2 meters.

93. For openings, deep trenches and pipe pits located next to vehicle driving lanes, the cover plates added to the trenches should be able to withstand a load no less than the local rated truck rear wheel effective bearing capacity (2 times).

94. The bottom of the stair feet should be solid and should not be used elevated. The appropriate working angle of the vertical ladder is (75°±5°).

95. When working in the air during concrete pouring, if there are no reliable safety facilities, you must fasten your seat belt and buckle the safety hook, or add a safety net.

96. Riggings, scaffolding boards, hanging baskets, cages, platforms and other equipment used for suspended operations must undergo (technical appraisal) or verification before they can be used.

97. When installing pipelines, there must be an existing structure or operating platform as a foothold. It is strictly prohibited to stand or walk on the pipeline during installation.

98. In addition to protective railings on both sides of various vertical transportation and material receiving platforms, (safety doors) or movable protective railings should also be installed at the platform entrance.

99. Temporary guardrails must be installed at stair entrances and stair sections in layered construction. Top stairwells should be installed as the structure progresses (formal protective railings).

100. The scrappage period of seat belts is (3-5 years).

101. The minimum safe operating distance between the perimeter of the project under construction (including scaffolding equipment) and the sideline of the 10KV external power overhead line should be (6 meters).

102. The minimum vertical distance when the motorway at the construction site intersects with the 220/380V overhead lines should be (6 meters).

103. When constructing in a tunnel, the lighting power supply voltage should not be greater than (36V). When constructing in a humid place, the lighting power supply voltage should not be greater than (24V).

104. When welding, it is strictly prohibited to use metal pipes, metal scaffolding, structural steel bars and other metal objects to overlap and replace (wires).

105. When arc welding, if a personal or mechanical accident occurs, the power supply should be cut off immediately.

106. When calcium carbide catches fire, you must use dry sand or (carbon dioxide) fire extinguisher. It is strictly forbidden to use other fire extinguishers or water to extinguish the fire.

107. In order to prevent the welding arc from damaging the eyes, the protective method that should be adopted is to use (filter).

108. In humid places and environments with a high risk of electric shock, the safe voltage is (12V).

109. According to the noise standards for industrial enterprises in my country, the allowable noise level for newly built, expanded or renovated enterprises is (85) decibels.

110. The carpentry work area at the construction site is a (level one fire area).

111. The fire permit at the construction site shall be approved by the (project leader) department.

112. (Tractors) are not allowed to enter flammable and explosive goods warehouses or stockyards for loading and unloading operations.

113. The door of the flammable and explosive goods warehouse should be opened (outward).

114. Acetylene cylinders used for gas welding should be placed away from open flames (10 meters).

115. If the bottleneck of the oxygen bottle freezes during winter construction, measures (hot water thawing method) should be taken to thaw it.

116. The safe distance between acetylene cylinders and oxygen cylinders used in welding and cutting operations is (5) meters.

117. Among the following items, (3) is flammable. 1. Asbestos tiles 2. Glass 3. FRP 4. Concrete

118. During winter construction, pay attention (anti-slip) when working at heights.

119. Temporary road arching during rainy season (4%).

Multiple choice questions:

1. Pipe jacking construction mainly includes: (1. Setting up the working pit, building the back and laying the guide rails 2. Laying out the jacking equipment, and preparing the working pipe 3 , precipitation and drainage, jacking 4, excavation and excavation, down pipe and joints)

2. The safety protection measures during the shield construction process include (1, shield machine hole entry, 2, shield. The machine advances the excavation, and the 3 shield machine exits the hole)

3. The sequence and method of earth excavation must be consistent with the design conditions and follow the following principles: (1. Excavate first and support 2. Excavation with support first 3. Excavation in layers 4. Excavation is strictly prohibited)

4. How to drain water during foundation pit excavation? (1. Set up a water collection well 2 at the bottom of the pit, and dig a drainage ditch around or in the center of the pit. 3. Lead the water into the water collection well 4, and then pump it out. 5. The pumped water should be diverted to prevent backflow.) < /p>

5. The bottom of the vertical pole of the fastener-type steel pipe formwork bracket should usually be set (1, base 2, full-length wooden pad)

6. The defects that steel pipes cannot be used are (1, Severe rust 2, severe bending 3, flattening 4, cracks)

7. Hooks and rings used in lifting operations must have a smooth surface and must not have (1. Cracking 2. Scores 3. Acute angle 4. Seam 5, crack).

8. When several jacks are working at the same time, the things to pay attention to are (1. Obey unified command 2. Make consistent movements 3. Ensure synchronous lifting 4. Ensure synchronous lowering)

9. During the climbing process of the tower crane, which of the following actions are prohibited? (1, lifting 2, luffing 3, turning 4, lifting and turning 5, lifting and luffing)

10. Crane The disassembly and assembly operations should be carried out during the day, and operations should be stopped when encountering (1, strong wind, 2, dense fog, 3, rain or snow).

11. It is strictly prohibited to operate the tower crane (1. pulling piles 2. cable-staying, tilting 3. rotating during jacking 4. lifting heavy objects to fall freely)

12. 1. There are special regulations for the setting of wall-connecting parts of glyph-shaped and open-shaped scaffolding. They are (1. Wall-connecting parts 2 must be set at both ends of the scaffold. The vertical spacing between the end wall-connecting parts should not be greater than the building floor height, and should not be More than 4 meters (two steps))

13. When using old fasteners, the following principles should be followed: (1. There are cracks. Deformed ones are strictly prohibited from use. 2. If there are slip wires, they must be replaced).

14. During the period of use of the scaffolding, it is strictly prohibited to dismantle (1, longitudinal and horizontal horizontal rods at the main nodes 2, wall-connecting parts 3, vertical and horizontal sweeping rods)

15. Edge Which of the following requirements should the upper pole of the protective railing meet? (1. Height from the ground: 1.0-1.2 meters, 2. Withstand external force 1000N)

16. Suspended operations should have a solid footing and must be configured according to the specific situation (1. Railings 2. Guardrails (Network)

17. Which of the following regulations regarding edge protection railings are correct? (1. The protective railing should be composed of upper and lower horizontal bars and railing posts2. The height of the lower bar from the ground is 0.5-0.6 meters3, and the height of the upper bar from the ground is 1.0-1.2 meters).

18. Carry out cross-cutting operations (1, floor edge 2, scaffolding edge 3, passage opening.)

19. The following protective measures for vertical openings on the ground are correct (1, install a switch-type safety door 2, install a tool-type safety door 3, use protective railings, set foot guards 4, and install a fixed safety door.)

20. Make the template The following points are correct for suspended operations during support and disassembly: (1. It is strictly prohibited to climb up and down on the connectors and supports; 2. It is strictly prohibited to install and dismantle the formwork on the same vertical surface; 3. When erecting the formwork for an airborne structure, you should When erecting brackets or scaffolding 4, if there are reserved holes on the formwork, the holes should be covered after installation. 5. For high-altitude operations such as formwork removal, climbing equipment or brackets should be equipped).

21. Protective railings must be installed when working at heights in the following locations. (1 around the foundation pit 2. around the awning 3, over the eaves 4, around the roof and floors without external scaffolding 5, around the material platform and the platform)

22. What is commonly referred to in construction The "three treasures" of construction refer to (1 safety helmet, 2 safety belts, 3 safety net)

23. The safety net consists of the following parts: (1, net body 2, side rope 3, tether 4, tendon rope )

24. Overhead lines can be erected on (1, wooden poles and 2 reinforced concrete poles.)

25. The underground facilities that can be used for natural grounding bodies include (1, reinforced concrete structures Body 2, metal well pipe 3, metal water pipe 4, steel armor for armored cables).

26. The applicable site conditions for 36V lighting are (1. High temperature; 2. Conductive dust; 3. Lamp height less than 2.5 meters).

27. The responsibilities of the electrician at the construction site are to undertake electrical engineering (1. Installation 2. Inspection 3. Maintenance 4. Dismantling).

28. Without taking corresponding safety measures, the following (1. Rooms where flammable and explosive dangerous goods are made, processed and stored 2. Storage tanks and containers for storing flammable and explosive dangerous goods 3. Live electricity Equipment 4, newly painted building components and equipment 5, containers containing flammable liquids that have not been thoroughly cleaned) are not allowed to weld and cut.

29. Pay attention to the safe use of gas cylinders (1. Prevent the gas cylinder from being heated 2. Operate it correctly 3. There should be residual gas at the end of use to prevent accidents caused by mixing other gases or impurities 4 , Strengthen the maintenance of gas cylinders, 5. Gas cylinder users are not allowed to change the filling type or change the color mark of the gas cylinder without authorization)

True or False Question:

1. Cable. The disassembly and assembly of the head must be done only after cutting off the power supply. (Yes)

2. The occurrence of quicksand is related to dynamic water pressure. Dynamic water pressure refers to the resistance of groundwater to particles during seepage. At the same time, the water produces a reaction force accordingly. This reaction force It is called hydrodynamic pressure. Yes

3. When the dynamic hydraulic force is equal to or greater than the water immersion intensity of the soil, it is in a suspended state. At this time, the shear strength of the soil is zero, and the soil particles flow together with the seepage water. This phenomenon is It's called quicksand.

True

4. Steel wire ropes can be used arbitrarily and overloaded. False

5. When the demolition project may cause danger to the safety of surrounding adjacent buildings, corresponding protective measures must be taken , if necessary, the people in the building should be evacuated and resettled. Yes

6. Before the demolition operation, the construction unit should check the condition of various pipelines in the building, and it is not necessary to confirm that all pipelines are cut off before construction can begin. Wrong

7. When the safe distance between the demolished building facing the street and the traffic road cannot meet the requirements, necessary safety measures must be taken. Yes

8. If unknown objects are found during the demolition project, the construction should be stopped, corresponding emergency measures should be taken to protect the site and reported to the relevant departments in a timely manner. Yes

9. When dismantling pipelines and containers, the type and chemical properties of the residues must be identified and appropriate measures must be taken before dismantling can be carried out. Yes

10. During driving or operation, no one is allowed to sit or stand anywhere on the loader except outside the cab. Yes

11. When going up or down a slope, the scraper should drive at a low speed and should not change gears midway. It should not slide in neutral when going down a slope. Yes

12. When the mixer is operating, when the hopper is raised, no one is allowed to stay under or pass under the hopper. Yes

13. When the mixer is used in an area with a long operation period, the support legs can be used to support it. Wrong

14. Drivers should obey any emergency stop signal given by anyone. For

15. For luffing jib and self-elevating tower cranes that have not yet been attached, placards are not allowed to be hung on the tower crane. True

16. When steel wire ropes are used as wind ropes for material hoisting cables, the diameter shall not be less than 9.3mm. True

17. When the wind force is above Level 4, the tower crane shall not carry out jacking operations. Yes

18. After a snowstorm or typhoon, safety facilities for working at heights should be inspected one by one. Yes

19. Other vertical holes and openings that pose a risk of falling to nearby people and objects should be covered or protected, and measures should be taken to fix their positions. Yes

20. When erecting or dismantling the protective shed, a warning area should be set up and a dedicated person should be assigned to monitor it. The upper and lower sides can be dismantled at the same time. Wrong

21. The resting point and upper tie point of the cantilevered steel platform. It should be installed on construction facilities such as scaffolding. Wrong

22. Protective railings must be installed on both sides of the derrick, construction elevators, scaffolding and building passages. Yes

23. Cable lines requiring three-phase four-wire power distribution must use five-core cables. Yes

24. Cable lines that require three-phase four-wire power distribution can be replaced by four-core cables plus an insulated wire. Wrong

25. When the construction site is stopped, the operation sequence when transmitting power is: when transmitting power, the main distribution box - distribution box - switch box. In the event of a power outage: switch box --- distribution box --- main distribution box.

26. The rated leakage operating current of the leakage protector in the switch box in general places shall not be greater than 30 mA, and the rated leakage operating time shall not be greater than 0.1 seconds. Yes

27. Acetylene bottles are strictly prohibited to be placed horizontally during transportation or use. Yes

28. It is prohibited to place objects, tools, or hang rubber hoses, welding torches, etc. on acetylene bottles.

29. Temporary fixing of welding parts is strictly prohibited by personnel cooperating with the welding operation. Yes

30. Oxygen cylinders should be equipped with anti-vibration rings and safety helmets. Yes

31. Employers shall not arrange workers with occupational taboos to engage in tabooed operations.

32. When performing welding operations in level 1, 2, and 3 hot areas, welders must hold an operating certificate for hot work. Wrong

33. The construction site should be equipped with fire exits, fire water sources, fire facilities and fire extinguishing equipment, and obvious signs should be set up at the entrance to the site. True

34. After heavy snowfall, the snow on the scaffolding and construction site must be cleared. Yes

35. Gas cylinders in use can be exposed to the scorching sun and can be located close to high-temperature areas, but the distance from an open flame should not be less than 10 meters.

Wrong

36. There are two anti-vibration rings on each cylinder. When the cylinder is hit, it can absorb energy, reduce vibration and protect the bottle logo and paint color from wear.

Case analysis questions:

1. A certain construction site placed the soil from the foundation pit on a brick wall 10 meters away from the foundation pit. On the outside of the wall is a In the primary school playground, the mounds of dirt are higher than the fence. After a heavy rain, one day while primary school students were having extra-curricular activities on the playground, the wall suddenly collapsed, crushing four primary school students who were playing beside the wall to death.

Determine whether the following is true or false:

1. The soil piled by the excavator should not be piled next to the fence. Yes

2. Primary school students should not play near the fence. Wrong

3. The excavation unit violated operating procedures. Wrong

4. When digging a foundation pit, the foundation trench should be piled with soil according to regulations.

2. A certain construction site was undergoing main construction, and no dense-mesh safety net was hung on the outside of the scaffolding. The wind was very strong that day. Zhang passed under the building and suddenly fell from the edge of the fifth floor slab. A 1-meter-long 4cm x 6cm square piece of wood hit Zhang on the head (without wearing a safety helmet), and he died after the hospital failed to rescue him.

1. Mainly caused by strong winds blowing off square logs. Wrong

2. A dense-mesh safety net was not hung on the outside of the scaffolding as required. Yes

Three. Zhang violated the regulations by not wearing a safety helmet. Yes

Four. Violation of the regulations that materials should be stacked stably when working at heights. For the above information, please refer to the examination question bank at the bottom of the homepage of the Construction Training Network. There are examination questions from previous years for reference only.