Influence of underground radio wave on human body in coal mine
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摘要: 5G,WiFi6,UWB,ZigBee等矿井移动通信系统及人员和车辆定位系统等发射的较大功率无线电波会影响煤矿井下作业人员健康,因此,需要研究煤矿井下无线电波对人体的影响。研究了电磁辐射对人体的作用:人体不同部位对电磁辐射吸收能力不同,电磁辐射对人体头部的影响最大。无线电波发射功率限值包括职业暴露限值和公众暴露限值两大类。职业暴露是指作业人员在电磁辐射环境中暴露时间不大于8 h。煤矿井下作业人员的工作时间为每班工作8 h(3班倒)或每班工作6 h(4班倒),因此,煤矿井下无线电波发射功率限值应选择全身职业暴露无线电波发射功率最小的限值6.28 W。为防止煤矿井下无线电波发射引起瓦斯爆炸,GB/T 3836.1—2021《爆炸性环境 第1部分:设备 通用要求》规定煤矿井下无线电波发射功率不大于6 W。因此,取得防爆合格证和矿用安全标志准用证的5G,WiFi6,UWB,ZigBee等矿井移动通信系统及人员和车辆定位系统等,在保证无线发射天线距固定岗位人员大于1 m的条件下,不会对煤矿井下作业人员造成伤害。Abstract: The large-power radio waves emitted by 5G, WiFi6, UWB, ZigBee and other mine mobile communication systems and personnel and vehicle positioning systems will affect the health of underground personnel. Therefore, it is necessary to study the influence of underground radio waves on human body. The influence of electromagnetic radiation on the human body has been studied. Different parts of the human body have different absorption capacities to electromagnetic radiation, and electromagnetic radiation has the greatest impact on the human head. Radio wave emission power limits include occupational exposure limits and public exposure limits. Occupational exposure means that the exposure time of the personnel in the electromagnetic radiation environment is no more than 8 hours. The working time of coal mine underground personnel is 8 hours per shift for 3 shifts or 6 hours per shift for 4 shifts. Therefore, the minimum limit value of 6.28 W of radio wave transmission power for whole-body occupational exposure shall be selected as the limit value of radio wave transmission power in the coal mine. In order to prevent the gas explosion caused by coal mine underground radio wave emission, GB/T 3836.1-2021 Explosive Atmospheres - Part 1: Equipment-General Requirements stipulates that the radio wave transmission power in coal mines shall not be greater than 6 W. Therefore, the 5G, WiFi6, UWB, ZigBee and other mine mobile communication systems and personnel and vehicle positioning systems that have obtained the explosion-proof certificate and the permit for the use of mining safety signs will not cause harm to the underground personnel of the coal mine under the condition that the distance between the wireless transmission antenna and the fixed post personnel is greater than 1 m.
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Key words:
- mine radio wave /
- occupational health and safety /
- electromagnetic radiation safety /
- 5G /
- WiFi6 /
- UWB /
- occupational exposure
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表 1 现有不同标准的SAR限值
Table 1. SAR limits of existing standards
标准名称 暴露类型 频率范围 全局SAR限值/
(W·kg−1)局部SAR限值
(头部和躯干)/(W·kg−1)局部SAR限值
(四肢)/(W·kg−1)IEEE Std C95.1—2019 职业暴露 100 kHz~6 GHz 0.4 10 20 公众暴露 100 kHz~6 GHz 0.08 2 4 ICNIRP 2020指南 职业暴露 100 kHz~6 GHz 0.4 10 20 6~300 GHz 0.4 — — 公众暴露 100 kHz~6 GHz 0.08 2 4 6~300 GHz 0.08 — — GB 21288—2007 公众暴露 30 MHz~6 GHz — 2 — GB 21288—2020(报批稿) 职业暴露 100 kHz~6 GHz — 10 20 公众暴露 100 kHz~6 GHz — 2 4 表 2 GB 9175—1988规定的电场强度和功率密度限值
Table 2. Limits for electric field strength and power density specified in GB 9175-1988
暴露等级 频率范围 电场强度/
(V·m−1)功率密度/
(W·m−2)一级(安全区) 0.1~30 MHz 10 — 30~300 MHz 5 — 300 MHz~300 GHz — 0.1 二级(中间区) 0.1~30 MHz 25 — 30~300 MHz 12 — 300 MHz~300 GHz — 0.4 表 3 GB 8702—1988规定的电场强度、磁场强度和功率密度限值
Table 3. Limits for electric field strength, magnetic field strength and power density specified in GB 8702-1988
暴露类型 频率范围 电场强度/
(V·m−1)磁场强度/
(A·m−1)功率密度/
(W·m−2)职业暴露 0.1~3 MHz 87 0.25 20 3~30 MHz $150/\sqrt f $ $0.4/\sqrt f $ $60/f$ 30~3 000 MHz 28 0.075 2 3~15 GHz $0.5\sqrt f $ $0.001\;5\sqrt f$ $f/1\;500$ 15~300 GHz 61 0.16 10 公众暴露 0.1~3 MHz 40 0.1 40 3~30 MHz $67\sqrt f $ $0.17\sqrt f $ $12/f$ 30~3 000 MHz 12 0.032 0.4 3~15 GHz $0.22\sqrt f $ $0.001\sqrt f $ $f/7\;500$ 15~300 GHz 27 0.073 2 注:f为频率,MHz。 表 4 GB 10437—1989规定的电场强度和功率密度限值
Table 4. Limits for electric field strength and power density specified in GB 10437-1989
波类型 频率范围 日暴露时间/h 电场强度/
(V·m−1)功率密度/
(W·m−2)连续波 30~300 MHz 4 19 1 8 14 0.5 脉冲波 30~300 MHz 4 14 0.5 8 10 0.25 表 5 GB 10436—1989规定的功率密度限值
Table 5. Limits for power density specified in GB 10436-1989
波类型 频率范围 日暴露时间 功率密度/
(W·m−2)连续波和脉冲波
(非固定辐射)300 MHz~300 GHz 8 h 0.5 小于或大于8 h 4/t 脉冲波
(固定辐射)300 MHz~300 GHz 8 h 0.25 小于或大于8 h 2/t 注:t为日暴露时间,h;短时间暴露最高功率密度一般不超过10 W/m2,若大于该值需使用个人防护,且不得大于50 W/m2。 表 6 GB 12638—1990规定的电场强度和功率密度限值
Table 6. Limits for electric field strength and power density specified in GB 12638-1990
波类型 频率范围 日暴露时间 电场强度/
(V·m−1)功率密度/
(W·m−2)连续波 30 MHz~
300 GHz8 h 14 0.5 小于或大于8 h — 4/t且不超过40 脉冲波 30 MHz~
300 GHz8 h 10 0.25 小于或大于8 h — 2/t且不超过20 表 7 GY 5054—1995规定的电场强度、磁场强度和功率密度限值
Table 7. Limits for electric field strength, magnetic field strength and power density specified in GY 5054-1995
暴露类型 频率范围 电场强度/
(V·m−1)磁场强度/
(A·m−1)功率密度/
(W·m−2)职业暴露
(8 h工作时间内)0.1~3 MHz 87 0.25 20 3~30 MHz $150/\sqrt f $ $0.4/\sqrt f $ $60/f$ 30~3 000 MHz 28 0.075 2 3~15 GHz $0.5\sqrt f $ $0.001\;5\sqrt f$ $f/1\;500$ 15~300 GHz 61 0.16 10 公众暴露
(24 h内)0.1~3 MHz 40 0.1 4 3~30 MHz $67/\sqrt f $ $0.17/\sqrt f $ $12/f$ 30~3 000 MHz 12 0.032 0.4 3~15 GHz $0.22\sqrt f $ $0.001\sqrt f $ $f/7\;500$ 15~300 GHz 27 0.073 2 表 8 GB 8702—2014规定的电场强度、磁场强度、磁感应强度和功率密度限值
Table 8. Limits for electric field strength, magnetic field strength, magnetic induction strength and power density specified in GB 8702-2014
频率范围 电场强度/
(V·m−1)磁场强度/
(A·m−1)磁感应
强度/μT功率密度/
(W·m−2)1~8 Hz 8 000 $32\;000/{f^2}$ $40\;000/{f^2}$ — 8~25 Hz 8 000 $4\;000/f$ $5\;000/f$ — 0.025~1.2 kHz $200/f$ $4/f$ $5/f$ — 1.2~2.9 kHz $200/f$ 3.3 4.1 — 2.9~57 kHz 70 $10/f$ $12/f$ — 57~100 kHz $4\;000/f$ $10/f$ $12/f$ — 0.1~3 MHz 40 0.1 0.12 4 3~30 MHz $67/{f^{0.5}}$ $0.17/{f^{0.5}}$ $0.21/{f^{0.5}}$ $12/f$ 30~3 000 MHz 12 0.032 0.04 0.4 3~15 GHz $0.22{f^{0.5}}$ $0.000\;59{f^{0.5} }$ $0.000\;74{f^{0.5} }$ $f/7\;500$ 15~300 GHz 27 0.073 0.092 2 注:f单位为频率范围对应单位。 表 9 GJB 5313A—2017规定的电场强度和功率密度限值
Table 9. Limits for electric field strength and power density specified in GJB 5313A-2017
暴露类型 频率范围 电场强度/
(A·m−1)功率密度/
(W·m−2)作业区短时间
(<1 h)暴露100 kHz~3.5 MHz 170 — 3.5~10 MHz $610/f$ — 10~400 MHz 61 10 400~2 000 MHz $3{f^{0.5}}$ $f/40$ 2~300 GHz 137 50 作业区连续波
8 h暴露0.1~3 MHz 47.7 6 3~30 MHz $82.5/{f^{0.5}}$ $18/f$ 30~3 000 MHz 15 0.6 3~10 GHz $0.274{f^{0.5}}$ $f/5\;000$ 10~300 GHz 27.4 2 生活区短时间
(<1 h)暴露0.1~3 MHz 40 4 3~30 MHz $67/{f^{0.5}}$ $12/f$ 30~3 000 MHz 12 0.4 3~15 GHz $0.22{f^{0.5}}$ $f/7\;500$ 15~300 GHz 27 2 生活区日暴露 0.1~3 MHz 33.8 3 3~30 MHz $58.5/{f^{0.5}}$ $9/f$ 30~3 000 MHz 10.6 0.3 3~10 GHz $0.194{f^{0.5}}$ $f/10\;000$ 10~300 GHz 19.4 1 表 10 IEEE Std C95.1—2019规定的电场强度、磁场强度和功率密度限值
Table 10. Limits for electric field strength, magnetic field strength and power density specified in IEEE Std C95.1-2019
暴露类型 频率范围 电场强度/(V·m−1) 磁场强度/(A·m−1) 基于电场强度的
功率密度/(W·m−2)基于磁场强度的
功率密度/(W·m−2)公众暴露(全身) 0.1~1.34 MHz 614 $16.3/f$ 1 000 $100\;000/{f^2}$ 1.34~30 MHz $823.8/f$ $16.3/f$ $1\;800/{f^2}$ $100\;000/{f^2}$ 30~100 MHz 27.5 $158.3/{f^{1.668}}$ 2 $9\;400\;000/{f^{3.336} }$ 100~400 MHz 27.5 0.0729 2 2 400~2 000 MHz — — $f/200$ $f/200$ 2~300 GHz — — 10 10 职业暴露(全身) 0.1~1 MHz 1 842 $16.3/f$ 9 000 $100\;000/{f^2}$ 1~30 MHz $1\;842/f$ $16.3/f$ $9\;000/{f^2}$ $100\;000/{f^2}$ 30~100 MHz 61.4 $16.3/f$ 10 $100\;000/{f^2}$ 100~400 MHz 61.4 0.163 10 10 400~2 000 MHz — — $f/40$ $f/40$ 2~300 GHz — — 50 50 公众暴露(局部) 0.1~1.34 MHz 1 373 $36.4/f$ 5 000 $500\;000/{f^2}$ 1.34~30 MHz $1\;842/f$ $36.4/f$ $9\;000/{f^2}$ $500\;000/{f^2}$ 30~100 MHz 61.4 $353/{f^{1.668}}$ 10 $47\;000\;000/{f^{3.336} }$ 100~400 MHz $21.2{f^{0.232}}$ $0.056\;2{f^{0.232} }$ $1.19{f^{0.463}}$ $1.19{f^{0.463}}$ 400~2 000 MHz — — $1.19{f^{0.463}}$ $1.19{f^{0.463}}$ 2~6 GHz — — 40 40 6~300 GHz — — $55{(f/1\;000)^{ - 0.177} }$ $55{(f/1\;000)^{ - 0.177} }$ 300 GHz — — 20 20 职业暴露(局部) 0.1~1 MHz 4 119 $36.4/f$ 45 000 $500\;000/{f^2}$ 1~30 MHz $4\;119/f$ $36.4/f$ $45\;000/{f^2}$ $500\;000/{f^2}$ 30~100 MHz 137.3 $36.4/f$ 50 $500\;000/{f^2}$ 100~400 MHz $47.3{f^{0.232}}$ $0.125{f^{0.232}}$ $5.93{f^{0.463}}$ $5.93{f^{0.463}}$ 400~2 000 MHz — — $5.93{f^{0.463}}$ $5.93{f^{0.463}}$ 2~6 GHz — — 200 200 6~300 GHz — — $274.8{(f/1\;000)^{ - 0.177} }$ $274.8{(f/1\;000)^{ - 0.177} }$ 300 GHz — — 100 100 表 11 ICNIPR 2020指南规定的电场强度、磁场强度和功率密度限值
Table 11. Limits for electric field strength, magnetic field strength and power density specified in ICNIPR 2020 guideline
暴露类型 频率范围 电场强度/
(V·m−1)磁场强度/
(A·m−1)功率密度/
(W·m−2)公众暴露
(全身)0.1~30 MHz $300/{f^{0.7}}$ $2.2/f$ — 30~400 MHz 27.7 0.073 2 400~2 000 MHz $1.375{f^{0.5}}$ $0.003\;7{f^{0.5} }$ $f/200$ 2~300 GHz — — 10 职业暴露
(全身)0.1~30 MHz $660/{f^{0.7}}$ $4.9/f$ — 30~400 MHz 61 0.16 10 400~2 000 MHz $3{f^{0.5}}$ $0.008{f^{0.5}}$ $f/40$ 2~300 GHz — — 50 公众暴露
(局部)0.1~30 MHz $671/{f^{0.7}}$ $4.9/f$ — 30~400 MHz 62 0.163 10 400~2 000 MHz $4.72{f^{0.43}}$ $0.012\;3{f^{0.43} }$ $0.058{f^{0.86}}$ 2~6 GHz — — 40 6~300 GHz — — $55/{(f/1\;000)^{0.177} }$ 300 GHz — — 20 职业暴露
(局部)0.1~30 MHz $1\;504/{f^{0.7} }$ $10.8/f$ — 30~400 MHz 139 0.36 50 400~2 000 MHz $10.58{f^{0.43}}$ $0.027\;4{f^{0.43} }$ $0.29{f^{0.86}}$ 2~6 GHz — — 200 6~300 GHz — — $275/{(f/1\;000)^{0.177} }$ 300 GHz — — 100 表 12 基于现有标准计算得到的无线电波发射功率限值
Table 12. Radio wave emission power limits calculated based on existing standards
标准名称 暴露类型 最小功率密度
限值/(W·m−2)发射功率
限值/WGB 9175—1988 一级(安全区) 0.1 1.25 二级(中间区) 0.4 5 GB 8702—1988 职业暴露(8 h) 2 25.12 公众暴露(24 h) 0.4 5 GB 10437—1989 连续波(8 h) 0.5 6.28 脉冲波(8 h) 0.25 3.14 GB 10436—1989 连续波和脉冲波
(非固定辐射)(8 h)0.5 6.28 脉冲波(固定辐射)(8 h) 0.25 3.14 GB 12638—1990 连续波(8 h) 0.5 6.28 脉冲波(8 h) 0.25 3.14 GY 5054—1995 职业暴露(8 h) 2 25.12 公众暴露(24 h) 0.4 5 GB 8702—2014 公众暴露 0.4 5 GJB 5313A—2017 作业区短时间
(<1 h)暴露10 125.6 作业区连续波8 h暴露 0.6 7.5 生活区短时间
(<1 h)暴露0.4 5 生活区日暴露 0.3 3.77 IEEE Std C95.1—2019
和ICNIPR 2020指南公众暴露(全身) 2 25.12 职业暴露(全身) 10 125.6 公众暴露(局部) 10 125.6 职业暴露(局部) 50 628 -
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