JP5600909B2 - Dismantling method for long members with toxic substance-containing members attached - Google Patents

Description

  The present invention relates to a dismantling method for a long member to which a harmful substance-containing member is attached.

  When removing a hazardous substance-containing member from a member to which a hazardous substance-containing member containing a harmful substance such as asbestos is attached, in order to prevent scattering of the harmful substance-containing member, for example, around the construction surface that becomes the hazardous substance-containing member surface Using a bag body having an opening that can enclose the construction surface, airtightly attach the opening of the bag body to the adjacent area of the construction surface so as to surround the construction surface, and contain harmful substances with a removal tool in the sealed bag body A method for removing a member is known (see, for example, Patent Document 1). In addition, when disassembling a member to which a harmful substance-containing member is attached, since the harmful substance-containing member scatters at the time of cutting or removing, the scattering of the toxic substance-containing member must be prevented.

Japanese Examined Patent Publication No. 3-68189

  However, when the member to which the toxic substance-containing member is attached is a long member that is long in a predetermined direction, it is difficult to airtightly surround the entire toxic substance-containing member. For this reason, when the member to which the toxic substance-containing member is attached is a long member, it is necessary to seal the entire space in which the long member is provided, and there is a problem that enormous costs may be required. is there.

  The present invention has been made in view of such a problem, and the object of the present invention is to provide a long material to which a harmful substance-containing member is attached that can disassemble the long member to which the harmful substance-containing member has been attached at low cost. The object is to provide a member dismantling method.

In order to achieve this object, the dismantling method for a long member to which a harmful substance-containing member of the present invention is attached is the above-mentioned harmful space in a sealed space provided along a circumferential direction intersecting the longitudinal direction of the long member. A first removing step of removing the substance-containing member, and a cutting step of cutting a part of the long member from which the harmful substance-containing member has been removed in the first removing step, and cutting off a part of the long member. And a carrying-in step of carrying in a part of the separated long member into the sealed facility; and a second step of removing a part of the harmful substance-containing member of the separated long member in the sealed facility. A removing step , wherein the harmful substance-containing member is attached to the outer peripheral surface of the long member, and the first removing step covers a part of the outer peripheral surface of the long member so as to be visible. Implemented in a cover member forming a working space, said cover A dismantling method of the elongated member which is pollutant member, wherein adhering that by the workspace wood covering is moved in the circumferential direction is removed along the pollutant member in the circumferential direction.
According to the dismantling method of the long member to which such a harmful substance-containing member is attached, the long member to be disassembled is harmful in the sealed space provided along the circumferential direction at the site to be cut before cutting. Since the substance-containing member is removed, the harmful substance-containing member is not attached to the site where the long member is cut. For this reason, it is possible to prevent scattering of the harmful substance-containing member by cutting the long member.

  Further, since the long member is cut at the site where the harmful substance-containing member has been removed, it is possible to cut the long member into a short size that is easy to transport without scattering the harmful substance-containing member. For this reason, it is possible to carry the separated part, which is a part of the long member, into the sealed equipment, and the hazardous substance-containing member attached to the separated part can be easily inside the sealed equipment. It is possible to remove. For this reason, in disassembling the long member to which the toxic substance-containing member is attached, it does not require a sealed space that covers the space where the long member is provided or can accommodate the entire long member. It is possible to disassemble the long member to which is attached at low cost.

Further, the removal of the harmful substance-containing member is carried out in a covering member that covers a part of the outer peripheral surface of the long member so as to be visible so as to form a work space, and thus covers the entire outer periphery of the long member. Therefore, it is possible to keep the work scale smaller than when removing the harmful substance-containing member. For this reason, it is possible to disassemble the long member to which the harmful substance-containing member is attached at a lower cost. In addition, since the hazardous substance-containing member is removed along the circumferential direction by moving the working space covered by the covering member in the circumferential direction, it is harmful over the entire circumference in the circumferential direction of the long member while keeping the work scale small. It is possible to remove the substance-containing member.

The dismantling method of the long member to which the harmful substance-containing member is attached may include a scattering prevention agent spraying step of spraying the scattering prevention agent on the site where the harmful substance-containing member is removed in the work space. desirable.
According to the dismantling method of the long member to which such a harmful substance-containing member is attached, the scattering agent is sprayed on the site where the harmful substance-containing member is removed in the work space, so the harmful substance-containing member is a covering member. The anti-scattering agent is sprayed in a state covered with water. For this reason, it is possible to prevent the harmful substance-containing member and the scattering inhibitor from scattering outside the work space. In addition, since the anti-scattering agent is sprayed before the cutting process for cutting off a part of the long member, the part containing the harmful substance-containing member is also sprayed when cutting the long member. It is possible to prevent scattering.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the demolition construction method of the elongate member to which the harmful substance containing member which can disassemble a harmful substance containing member cheaply was attached.

It is a figure for demonstrating the dismantling construction method of the elongate member to which the harmful substance containing member which concerns on this invention adhered. It is a figure which shows the operation | movement procedure of the dismantling method of the elongate member to which the harmful substance containing member which concerns on this invention adhered. It is a figure for demonstrating the structure of the cover member used for the dismantling method of the elongate member to which the harmful substance containing member adhered. It is a schematic diagram of the front for demonstrating the removal apparatus of the harmful substance containing member used at a removal process.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a view for explaining a dismantling method for a long member to which a harmful substance-containing member according to the present invention is attached. FIG. 2 is a diagram showing a work procedure of a dismantling method for a long member to which a harmful substance-containing member according to the present invention is attached.

  In the present embodiment, as a long member to which a harmful substance-containing member containing a harmful substance such as asbestos is attached, for example, it passes through the indoor space 8 of the building, and heat insulation as a harmful substance-containing member is formed on the outer peripheral surface 1a of the pipe body 2. The dismantling method of the large pipe 1 to which the material 3 is attached will be described as an example. The pipe main body 2 of the large-sized pipe 1 of the present embodiment is a large-diameter pipe whose inner diameter exceeds 1 m.

  As shown in FIGS. 1 and 2, the dismantling method for the large-sized pipe 1 to which the heat insulating material 3 of the present embodiment is attached is performed in a sealed work space 12 provided along the circumferential direction of the large-sized pipe 1. 1st removal process S1 which removes the heat insulating material 3, the scattering prevention agent spraying process S2 which sprays a scattering prevention agent to the site | part 1d from which the heat insulating material 3 was removed, and the site | part 1d from which the heat insulation material 3 of the large sized pipe 1 was removed Cutting step S3 for cutting off a part of the large-sized pipe 1, cutting-in step S4 for carrying a part of the separated large-sized pipe 1 into the work room 5 as a sealed facility, and a part of the separated large-sized pipe 1 And a second removing step S5 for removing the heat insulating material 3 in the working chamber 5.

  When the large pipe 1 to which the heat insulating material 3 is attached is disassembled as it is, the heat insulating material 3 as a harmful substance-containing member attached to the outer peripheral surface 1a is scattered. For this reason, for example, when cutting the large pipe 1, it is necessary to cut the site where the cutting work is performed in a sealed state, and the work such as curing and equipment for the entire site becomes large, and the cost increases. For this reason, in the dismantling method of the large pipe 1 to which the heat insulating material 3 is attached according to the present embodiment, after the large pipe 1 is divided into short sizes, the heat insulating material 3 is removed in the sealed working chamber 5 narrower than the site. I am going to do that. And since there is a possibility that the heat insulating material 3 may be scattered when the large pipe 1 is divided, the heat insulating material 3 in the vicinity of the part to be cut is covered in the first removal step by covering only the part to be cut before cutting. Have been removed.

  In the first removal step, the heat insulating material 3 is removed over the entire circumferential direction in a predetermined width in the longitudinal direction of the large-sized pipe 1 using the heat insulating material 3 removing device 10. For example, a part of the large pipe 1 in the circumferential direction is covered with a covering member 20 included in the heat insulating material 3 removing device 10 to form a sealed working space 12, and the heat insulating material 3 is removed and removed in the working space 12. After spraying the anti-scattering agent on the part 1d, the covering member 20 is moved in the circumferential direction, and the work of removing the heat insulating material 3 in the portion covered with the moved covering member 20 is repeated.

  FIG. 3 is a view for explaining the configuration of the heat insulating material removing apparatus used in the dismantling method of the long member to which the heat insulating material is attached. FIG. 4 is a schematic front view for explaining the heat insulating material removing device used in the removing step.

  The heat insulating material removing device 10 covers a portion 1b in the circumferential direction of the outer peripheral surface 1a of the large pipe 1 with the heat insulating material 3 attached to the pipe body 2 so as to be visible, and forms work spaces 12 and 14 (FIG. 3). As an engagement member that is provided on the member 20, the housing member 16 that accommodates and is removed from the work space 12 and that is removed from the work space 12, and the engagement member that is attached to the outer peripheral surface 1a and engages the cover member 20. And a work glove part 18 that is provided on the cover member 20, is partitioned from the work spaces 12 and 14, is inserted into the work spaces 12 and 14 from the outside of the cover member 20, and accommodates an operator's hand. ,have.

  The covering member 20 includes, for example, a plurality of resin-made frames 21 and a sheet member 22 that is attached to the plurality of frames 21 so that the plurality of frames 21 can be arranged at appropriate intervals.

  The frame 21 is an elongate member bent in, for example, a “U” shape, the opened side of the “U” shape is disposed on the outer peripheral surface 1a side, and the closed side is positioned on the opposite side to the outer peripheral surface 1a. To be arranged. In the following description, for each frame 21, the “U” -shaped open side is referred to as the open side of the frame 21, and the “U” -shaped closed side is referred to as the closed side of the frame.

  The sheet member 22 is a transparent or translucent member having flexibility, and a plurality of (here, seven) frames 21 are arranged so that their U-shaped portions face each other. The portion corresponding to the outer contour of the U-shape and the inner portion of the U-shape formed by the frames 21a and 21b located at both ends are formed. In addition, at several places between the adjacent frames 21, openings 22a are provided so as to be opposed to each other so as to be positioned on the open side of the frames 21 and to which the work gloves 18 are attached. The sheet member 22 is formed in a bellows shape by being bent a plurality of times between the frames 21 adjacent to each other.

  The covering member 20 of the present embodiment is configured such that seven frames 21 are joined to each other at a distance from each other by a sheet member 22 and are extendable in a direction in which the frames 21 are connected (hereinafter referred to as an expansion / contraction direction). Has been. For this reason, since each frame 21 has a high degree of freedom in the expansion and contraction direction, the distance between the open side and the closed side of the frame 21 increases or decreases between the frames 21. For this reason, the covering member 20 is curved so that the frames 21a and 21b at both ends in the expansion / contraction direction are positioned closer to the closing side than the center frame 21c, or the frames 21a and 21b at both ends are opened from the center frame 21c. It is possible to bend so as to be located on the side, and to change the curvature of the curve easily. And when this covering member 20 is installed in the outer peripheral surface 1a of the large sized pipe 1, the inner side of the covering member 20 will become the work spaces 12 and 14. And the magnitude | size of the covering member 20 is the state where the covering member 20 was extended | stretched, for example, the length of the expansion-contraction direction is 900 mm, the width between the edge parts of the flame | frame 21 is 350 mm, and height is 350 mm. In the following description, the distance between the ends of the frame 21 is referred to as the width of the covering member.

  In the opening 22a provided at a position facing the sheet member 22, the work glove part 18 having a glove-shaped tip is attached in an airtight manner without forming a gap between the opening 22a and the opening 22a. It has been. The work glove part 18 is formed at the center of the work spaces 12 and 14 formed by the frame 21 and the sheet member 22 when the operator inserts his / her hand through the opening 22a provided at the opposite position. It has a reachable length.

  The housing member 16 is formed integrally with the sheet member 22 constituting the covering member 20, and is provided at a portion that covers one end portion of the covering member 20 in the expansion / contraction direction. That is, the accommodating member 16 is provided at either end of the covering member 20, forms a space communicating with the work spaces 12, 14, and is disposed so as to protrude outward of the work spaces 12, 14. For this reason, the heat insulating material 3 that has been removed is accommodated outside the outer peripheral surface 1 a in the work spaces 12 and 14.

  The band 30 is, for example, a flat rubber band provided longer than the outer peripheral length of the large-sized pipe 1 that is a work object, and a hook-and-loop fastener (not shown) is provided at the end. For this reason, the band 30 can be attached to the large-sized pipe 1 by winding the band 30 around the outer periphery of the large-sized pipe 1 and joining the ends with a hook-and-loop fastener.

  In the first removal step, first, the band 30 is attached to the outer peripheral surface 1 a of the large-sized pipe 1. At this time, two bands 30 are used, and are arranged so as to sandwich the work place on the outer peripheral surface 1a of the large-sized pipe 1 with a space between each other in the longitudinal direction of the large-sized pipe 1. The distance between the two bands 30 is slightly wider than the width of the covering member 20, that is, the width of the frame 21 (350 mm).

  Next, the covering member 20 provided with the housing member 16 and the work glove part 18 is disposed so as to cover the work location on the outer peripheral surface 1a of the large-sized pipe 1. At this time, for example, a removal tool and a heat-preventing agent for the heat insulating material 3 necessary for removing the heat insulating material 3 are arranged in the region covered with the covering member 20. Further, the covering member 20 is arranged in an extended state so that the expansion / contraction direction is along the circumferential direction of the large-sized pipe 1, and the covering member 20 is arranged outside in the width direction of the arranged covering member 20, that is, a frame. The covering member 20 is disposed so that the band 30 is located outside the sheet member 21 and the sheet member 22. At this time, the space surrounded by the covering member 20 becomes the work space 12. Further, the band 30 is brought into contact with the outer peripheral surface 1a so as to be bridged between the two bands 30 between the open end portions of the frames 21a and 21b at both ends in the extending / contracting direction of the covering member 20. Is provided.

  Next, the band 30 attached to the large-sized pipe 1 and the cover member 20 disposed on the outer peripheral surface 1a are joined over the entire circumference with a tape member 31 such as a cloth adhesive tape, for example, and the inside of the work space 12 is sealed. To do.

  The operator inserts a hand into the work glove part 18 from the outside of the work space 12, and scrapes off the heat insulating material 3 using a removal tool arranged in the work space 12. The heat insulating material 3 that has been scraped off is stored in a storage member 16 that communicates with the work space 12. After removing the heat insulating material 3 on the outer peripheral surface 1a in the first work space covered with the covering member 20, the scattering preventing agent is sprayed (scattering preventing agent spraying step S4).

  After removing the heat insulating material 3 in the work space 12 and spraying the anti-scattering agent to eliminate the risk of the heat insulating material 3 being scattered, the covering member 20 is replaced with another portion 1c different from the portion 1b of the outer peripheral surface 1a. The covering member 20 is moved to form a new work space 14 by being arranged in the position. At this time, first, the tape member 31 is peeled off in order to move the covering member 20 forming the working space 12.

  Next, the cover member 20 is contracted by pulling the one end 20a side of the cover member 20 on the side where the storage member 16 is not provided in the expansion / contraction direction to the other end 20b side, that is, the side where the storage member 16 is provided. At this time, when the heat insulating material 3 removed is packed in the housing member 16 and cannot be continuously used, a new housing member 16 is attached. At this time, the connecting portion between the housing member 16 and the sheet member 22 is sealed with the clamp member 23 and cut at the cover member 20 side of the sealed portion. Thereafter, a new accommodating member 16 is attached to the cut end portion of the sheet member 22 in an airtight manner.

  Next, the other end 20b side of the covering member 20 to which the accommodating member 16 is newly attached is extended in a direction away from the one end 20a side where the accommodating member 16 is not provided, so that the covering member 20 is formed on the outer peripheral surface 1a. A new work space 14 is formed by arranging in another part 1c different from the part 1b. At this time, an anti-scattering agent for the removing tool and the heat insulating material 3 is disposed in the region covered with the covering member 20. Moreover, the covering member 20 arrange | positions the covering member 20 so that the band 30 may be located in the outer side in the width direction of the arrange | positioned covering member 20, ie, the outer side of the flame | frame 21 and the sheet | seat member 22. FIG. At this time, the space surrounded by the cover member 20 moves along the circumferential direction of the large-sized pipe 1, and the moved cover member 20 becomes a new work space 14.

  The band 30 attached to the large-sized pipe 1 and the cover member 20 disposed on the outer peripheral surface 1a are joined by the tape member 31, and the inside of the new work space 14 is sealed.

  Then, the operator inserts his / her hand into the work glove part 18 from the outside of the new work space 14 and scrapes off the heat insulating material 3 using the removing tool disposed in the new work space 14. The heat insulating material 3 that has been scraped off is stored in a storage member 16 that communicates with the new work space 14. After removing the heat insulating material 3 on the outer peripheral surface 1a in the new work space 14 covered with the covering member 20, the anti-scattering agent is sprayed.

  Thus, after removing the heat insulating material 3 of the part 1b in the circumferential direction of the outer peripheral surface 1a of the large-sized pipe 1, the operation of moving the covering member 20 in the circumferential direction and removing the heat insulating material 3 of the other part 1c is repeated. Then, it is possible to remove the heat insulating material 3 in the region connected in the circumferential direction of the outer peripheral surface 1a of the large-sized pipe 1.

  Next, the two bands 30 and the covering member 20 are installed in the longitudinal direction of the large-sized pipe 1 from the region where the heat insulating material 3 has already been removed, at a position spaced apart by the length to be separated. The heat insulating material 3 in the region connected in the circumferential direction of the outer peripheral surface 1a is removed in the same manner as described above. Thereby, the site | part from which the heat insulating material 3 was removed is formed in the position separated from the large-sized piping 1 by the length for which it wanted to cut | disconnect.

  Next, in the cutting step S3, the covering member 20 is removed from the large-sized pipe 1, and the parts 1d (two places) from which the heat insulating material 3 has been removed are cut by the cutter 50 or the like. At this time, the part to be cut is cut in a state of being supported by the crane 51, a support base, or the like. In the part to be cut, the heat insulating material 3 has already been removed and the anti-scattering agent has been sprayed, so that the heat insulating material 3 is not scattered by the cutting operation.

  Next, the cut part of the large-sized pipe 1 is carried into the sealed working chamber 5 by the crane 51, a carriage, a conveyor, etc. (carrying-in process S4).

  The work chamber 5 is a room that is maintained at a pressure lower than the outdoor pressure (atmospheric pressure), for example, and is cured so as to seal the inside of the work chamber 5 against the outside air. For example, a PET sheet (PET sheet) is affixed so as to block the indoor and outdoor passages, so that air from the indoors does not flow out of the room, and harmful substance-containing members such as the heat insulating material 3 are moved out of the room. Prevents outflow.

  Outside the room, a negative pressure dust collector (not shown) is installed to suck indoor air, filter the air with a filter, remove harmful substances contained in the air, and exhaust it outside the room. It is configured.

  In addition, a PET sheet is also provided at the entrance / exit of the worker, and a small air flow path is provided between the outside air and the room by attaching the PET sheet like a curtain. This is because indoor air is sucked out by the negative pressure dust collector, so that outside air can be taken in and the atmospheric pressure in the room does not become lower than necessary.

In such a work room 5, the heat insulating material 3 adhering to the outer peripheral surface 1a of the cut | disconnected site | part of the large sized pipe 1 is scraped off by the removal tool by the worker who wears dust-proof clothing (second removal) Step S5).

  In this way, the large-sized pipe 1 is cut into a size that can be carried into the work chamber 5, and the heat insulating material 3 is removed in the work chamber 5, so that the heat insulating material 3 can be removed without increasing the work scale. It is possible to dismantle the large pipe 1 to which the heat insulating material 3 is attached without being scattered.

  According to the dismantling method of the large-sized pipe 1 to which the heat insulating material 3 of the present embodiment is attached, the large-sized pipe 1 to be disassembled is in the covering member 20 provided along the circumferential direction at the site to be cut before cutting. Since the heat insulating material 3 is removed in the sealed work space 12, the heat insulating material 3 does not adhere to the portion where the large-sized pipe 1 is cut. For this reason, it is possible to prevent the heat insulating material 3 from being scattered by cutting the large pipe 1.

  Further, since the large pipe 1 is cut at a site where the heat insulating material 3 is removed, the large pipe 1 can be cut into a short size that is easy to transport without scattering the heat insulating material 3. For this reason, a part of the separated large-sized pipe 1 can be carried into the work chamber 5 as a sealed facility, and the heat insulating material 3 adhering to the separated part is surely contained in the work chamber 5. Can be removed. For this reason, in the dismantling of the large-sized pipe 1 to which the heat insulating material 3 is attached, the indoor space 8 where the large-sized pipe 1 is provided is not covered, and a large sealed space that can accommodate the entire large-sized pipe 1 is not required. Therefore, it is possible to disassemble the large-sized pipe 1 to which the heat insulating material 3 is attached at low cost.

  Further, since the heat insulating material 3 is removed in the covering member 20 that covers the part 1b of the outer peripheral surface 1a of the large-sized pipe 1 so as to be visible and forms the work space 12, the outer peripheral surface 1a of the large-sized pipe 1 is removed. It is possible to keep the work scale smaller than when the heat insulating material 3 is removed covering the entire circumference. For this reason, it is possible to disassemble the large-sized piping 1 to which the heat insulating material 3 adheres at a lower cost. In addition, since the heat insulating material 3 is removed along the circumferential direction by moving the working space 12 covered by the covering member 20 in the circumferential direction, the heat insulating material is spread over the entire circumference of the large-sized pipe 1 while keeping the work scale smaller. 3 can be removed.

  Further, since the scattering preventing agent is sprayed on the portion 1d from which the heat insulating material 3 is removed in the work space 12, the scattering preventing agent is sprayed in a state where the portion 1d from which the heat insulating material 3 has been removed is covered. For this reason, it is possible to prevent the heat insulating material 3 from scattering outside the work space 12. Further, since the anti-scattering agent is sprayed on the portion 1d from which the heat insulating material 3 has been removed before the cutting step S3 for cutting off a part of the large pipe 1, the heat insulating material 3 is scattered when the large pipe 1 is cut. It is possible to prevent this.

<Other embodiments>
Moreover, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof.

  In the said embodiment, although the work target object was the cylindrical large-sized piping 1, the cross section makes a rectangular shape and the duct etc. which the harmful substance containing member adhered may be sufficient. In this case, for example, a cover member that covers a portion corresponding to one side of the rectangular shape in the circumferential direction may be used, and the harmful substance-containing member may be removed in four steps.

  Moreover, in the said embodiment, although the example which has comprised the bellows shape which the covering member 20 can expand-contract was demonstrated, it is not this limitation. For example, the covering member does not need to expand and contract, and may be a transparent covering member formed in a tunnel shape and having translucency. Further, the work object is not limited to a hollow member.

  In the implementation liquid, in the first removal step, an example in which a part of the outer peripheral surface of the large pipe 1 covered by the covering member is sequentially moved to remove the heat insulating material 3 of the large pipe 1 along the circumferential direction has been described. However, the method is not limited to this, and any method may be used as long as the heat insulating material 3 can be removed along the circumferential direction so that the large pipe 1 can be cut.

1 large pipe, 1a outer peripheral surface, 1b part, 1c other part,
1d Location where the heat insulating material is removed, 2 piping body, 3 heat insulating material, 5 working room,
8 indoor space, 10 heat insulating material removing device, 12 working space, 14 working space,
16 accommodating member, 18 working glove part, 20 covering member, 20a one end of covering member,
20b The other end of the covering member, 21 frame, 21a frame, 21c frame,
22 sheet member, 22a opening, 23 clamp material, 30 band,
31 Tape material

Claims (2)

It is a dismantling method of a long member to which a harmful substance-containing member is attached,
A first removal step of removing the harmful substance-containing member in a sealed space provided along a circumferential direction intersecting the longitudinal direction of the long member;
A cutting step of cutting a part of the long member from which the harmful substance-containing member has been removed in the first removing step, and cutting off a part of the long member;
A carrying-in process of carrying a part of the separated long member into a sealed facility;
A second removing step of removing a part of the toxic substance-containing member of the separated long member in the sealed facility;
Have
The harmful substance-containing member is attached to the outer peripheral surface of the long member,
The first removing step is performed in a cover member that covers a part of the outer peripheral surface of the long member so as to be visible and forms a work space, and moves the work space covered by the cover member in the circumferential direction. A method for disassembling a long member having a harmful substance-containing member attached thereto, wherein the harmful substance-containing member is removed along a circumferential direction . A dismantling method for a long member to which the harmful substance-containing member according to claim 1 is attached,
A dismantling method for a long member to which a harmful substance-containing member is attached, comprising a scattering agent spraying step of spraying a scattering inhibitor on a portion of the work space from which the harmful substance-containing member has been removed.

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