5.3.2 Anti-static Clothes
1.Basic Structure and Function of Anti-static Clothes
(1)Basic structure
①The anti-static clothes for live working are made of special anti-static clean fabric.The fabric shall be special polyester filament yarn,with conductive fiber braided longitudinally or latitudinally.
②Different styles are provided according to the grade requirements,and it shall be sewed with conductive fiber to maintain the electrical continuity of each part of the clothes.The sleeve and pants have a unique double-layer structure,with conductive or anti-static threads in the inner layer to meet the requirements of a high-grade dust-free environment.
③The whole set of high voltage anti-static clothes include coat,pants,hat,gloves and shoes,as shown in Fig.5-30.
Fig.5-30 Anti-static Clothes
(2)Basic function
①The anti-static clothes preventing the static agglomeration of clothing are sewn with anti-static fabric,with efficient and permanent anti-static,dust-proof performance,as well as the characteristics of thinness,slipperiness and clear texture.
②It can effectively protect the human body from high voltage electric field and electromagnetic wave.
③It is used for tower climbing(frame)operators of transmission line and substation and ground operators who need to prevent electrostatic induction.
2.Classification and Technical Specifications of Anti-static Clothes
(1)Classification
The anti-static clothes has a split,one-piece,pullover and other styles,and socks,hats and masks can be freely combined.According to the distribution of conductive components in the fiber,the conductive fibers can be divided into 3 types:homogeneous conductive components,covered conductive components and composite conductive components.
(2)Technical specifications
①The shielding efficiency shall not be less than 28db,the resistance of apparel fabric shall not be greater than 300Ω,and the resistance of shoes shall not be greater than 500Ω.
②The apparel fabric shall have a large permeation volume,so that wearers can feel comfortable.The air flow through the apparel fabric shall not be less than 35L/(m·2s).(https://www.daowen.com)
③When all anti-static clothes are made of anti-static fabric,without lining.When the lining(pocket,reinforcing cloth,etc.)must be used,its exposed area accounts for less than 20%of the exposed area of all the inner surface of the anti-static clothes;mask and lining shall be detachable when it accounts for more than 20%(e.g.,cold protective clothing or special clothing).
3.Inspection Contents of Anti-static Clothes
(1)Emphasis is placed on checking the anti-static clothes for any additional or worn metal items.
(2)After wearing for a period of time,the anti-static clothes shall be inspected.If the electrostatic performance does not meet the requirements,the anti-static clothes shall not be used again.
(3)The appearance shall be free from breakage,spots,dirt and other defects that affect the insulation performance.
(4)Metal accessories shall not be used on the clothes in general.Metal accessories shall not be exposed directly when they must be used(buttons,zippers,etc.).
4.Usage of Anti-static Clothes
(1)Under normal circumstances,when the explosive gas mixture continuously and frequently emerges or exists for a long time,or when the explosive gas mixture is likely to appear,the minimum ignition energy of the combustible material shall be less than 0.25mJ,and the anti-static clothes shall be worn.
(2)Do not wear and take off anti-static clothes on flammable and explosive occasions.
(3)Do not attach or wear any metal items to the anti-static clothes.
(4)When the anti-static clothes are worn,anti-static shoes shall also be worn,and the ground shall be anti-static floor with grounding system at the same time.
(5)High voltage electrostatic protective clothes shall not be used as equipotential shielding clothes.
5.Precautions for Storage of Anti-static Clothes
(1)The newly sewn clean anti-static clothes can be washed directly,and the recycled clean worn anti-static clothes shall be carefully removed for oil stain(if any)before washing procedures.After washing,drying is carried out in a special clean air circulation system.After washing and drying,folding is carried out in a special clean room for washing.They shall be put into a clean polyester bag or pocket,and double-layer packaging or vacuum plastic sealing can be carried out as required.
(2)The anti-static clothes shall be stored in ventilated dry tools and instruments warehouse as far as possible.And they shall be placed on a upper shelf in a special tools and instruments box.
6.Test Contents of Anti-static Clothes
The test contents of anti-static clothes are mainly the shielding efficiency test of the whole set of protective clothes,with the test period of half a year.