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Indoor air quality standards

by:HoldPeak     2020-05-18

indoor air quality standards:

indoor air quality standards ( GB / T 18883 - 2002). Appendix A

appendix A

( Normative appendix) Indoor air monitoring technology

A. Scope of 1

this appendix shall click on request when the indoor air monitoring, sampling time and frequency, sampling method and instrument, the various parameters in indoor air testing method, testing results and evaluation, quality assurance measures.

。 2 click on request

A. 2. 1 the number of sampling points: the number of sampling points according to the monitoring indoor area and site condition and determine the size, in order to correctly reflect the level of indoor air pollutants. In principle, less than 50 m2 room should be set ( 1 ~ 3) A point; Set (50 m2 and 100 m2 3 ~ 5) A point; More than 100 m2 at least five points. On the diagonal or quincunx evenly distributed.

。 2. 2 sampling points to avoid air vents, distance from the wall should be greater than zero. 文献。

。 2. 3 the height of the sample point: in principle is consistent with the person's breathing zone height. Relative height of 0. 5米~ 1。 Between 5 m.

。 3 sampling time and frequency

the annual average concentration sampling at least three months, daily average concentration in the sampling at least 18 h, 8 h average concentration sampling at least 6 h, 1 h average concentration at least 45 min sampling, sampling time should cover a period of poor ventilation zui.

。 4 sampling method and sampling instrument

according to the pollutants in the indoor air condition, choosing appropriate sampling method and instrument for indoor sampler noise should be less than 50 db ( 一) 。 Sampling methods should be according to the method specified in the test method of various pollutants and operation steps.

。 4. 1 screening method of sampling, sampling before 12 h closed doors and Windows, close the doors and Windows when sampling, the sampling at least 45 min.

。 4. 2 accumulation method, sampling: when filtering method is used to sample can not meet the requirements of this standard, must have a cumulative method ( According to the annual average, the average daily, 8 h average) The requirements of sampling.

。 5 quality assurance measures

A. 5. 1 seal check: motivated sampler for sampling system tightness before sampling inspection, shall not leak.

。 5. 2: flow calibration flow to maintain a constant sampling system, the sampling before and after sampling to use level 1 soap film meter calibration sample system inlet flow rate, error less than 5%. Sampler flow calibration: in sampler use normally, use level of soap film meter calibration sampler flowmeter calibration, calibration of 5 points, draw flow standard curve. Calibration record of atmospheric pressure and temperature.

。 5. 3 blank inspection: in a number of field sampling, should have two sample tube not sampling, and press the other sample tube, as a blank in the process of sampling inspection, if the blank test more than control, is this batch of samples.

。 5. 4 instrument before use, should according to the instrument manual for inspection and calibration instruments.

。 5. 5 when calculating the concentration of application type sampling volume conversion into standard under the condition of volume:

type:

where V0 converted to standard condition of sample volume, L;

V sampling volume, L;

T0 standards of the state of the temperature, the 273 K;

T sampling temperature at the scene of the sample point ( t) With the standards of the state of the temperature, the sum of ( t + 273) K;

P0 standard state under atmospheric pressure, 101. 3 kpa;

。 5. 6 each parallel sampling, the difference between the measurement and comparison of the average relative deviation is less than 20%.

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