GB/T 39990-2021Particulates - Bioaerosol samplers - Technical specification (English PDF)

4.2 Composition...

4.2.5 Sampling information record and storage unit

4.2.5.1 The sampler shall be able to automatically measure and display the instantaneous airflow ratio and sampling time; the display update time shall not exceed 5 s. The cumulative working condition sampling volume and the standard condition sampling volume shall be calculated once in at least 1 min.

4.2.5.2 The sampling information record and storage unit shall at least be able to record and store information, such as: sampling date, sampling time, ambient temperature, ambient atmospheric pressure, sampling No., sampling airflow ratio, sampling volume and standard condition sampling volume, etc.

4.2.5.3 It shall be able to transmit the stored record information to a computer or other carriers for query or printing, and the data shall be stored for at least 3 months.

4.3 Working Conditions

4.3.1 Ambient temperature: -10 °C ~ 50 °C.

4.3.2 Ambient humidity: relative humidity is not greater than 85%.

4.3.3 Atmospheric pressure: 80 kPa ~ 106 kPa.

5.3 Sampling Airflow Ratio

5.3.1 The indication error of the sampling airflow ratio shall not exceed ± 5%.

5.3.2 The repeatability of the sampling airflow ratio shall not be greater than 2%.

5.3.3 The stability of the sampling airflow ratio shall not exceed 5%.

6.2.6 Aerodynamic particle size spectrometer The maximum allowable indication error is: ± 30%FS.

6.2.7 Fluorescence spectrophotometer The maximum allowable indication error of wavelength is: ± 2 nm.

6.2.8 Aerosol generator 0.5 µm ~ 15 µm particles can be generated.

6.2.9 Constant-temperature biochemical incubator The temperature deviation is: ± 1.0 °C.

6.2.10 Reference standard sampler Andersen six-stage sampler air microbial sampler or AGI-30 air microbial sampler, with a sampling efficiency of not less than 70%.

6.3 Reagents or Materials

6.3.1 Monodisperse fluorescent polystyrene microspheres The sizes of the microspheres are respectively: 1 µm, 3 µm, 5 µm and 10 µm; the coefficient of variation is 3% ~ 5%.

6.3.2 Indicator microorganisms for inspection Certified standard substance of Serratia marcescens, certified standard substance of bacteriophage PHiX174 and certified standard substance of Bacillus atrophicus.

7.1 Sampling Efficiency

7.1.1 In the aerosol laboratory shelter, the sampling ports of the sampler to be tested and the filter membrane-type sampler have the same height, and the distance from the aerosol inlet is

0.5 m ~ 1 m. Use the aerosol generator to generate 1 µm monodisperse fluorescent microsphere aerosol. 5 min after generation, use an aerodynamic particle counter to respectively measure the concentration of aerosol particles at the sampling ports where the sampler to be tested and the filter membrane-type sampler are located.

7.1.2 After the two measured concentrations reach the same level, simultaneously turn on the sampler to be tested and the filter membrane-type sampler for aerosol sampling for 5 min. to culture and count the collected samples, so as to obtain the number of viable microorganisms collected by each sampler. The number of biological particles collected by the sampler to be tested is Ntest-vc; the sum of the number of biological particles collected by the sampler to be tested and the number of biological particles collected by the filter membrane-type sampler on the gas circuit is the total number of biological particles on the gas circuit Ntext-tot. The number of biological particles collected by the reference standard sampler is Nref-vc; the sum of the number of biological particles collected by the reference standard sampler and the number of biological particles collected by the filter membrane-type sampler on the gas circuit is the total number of biological particles on the gas circuit Nref-tot.

7.2.5 In accordance with Formula (2) and Formula (3), respectively calculate the survival rate of microbial Stest-eff of the sampler to be tested and the survival rate of microbial Sref-eff of the reference standard sampler: Where, Stest-eff

---the survival rate of microbial of the sampler to be tested; Ntest-vc

---the number of biological particles collected by the sampler to be tested; Ntext-tot

---the total number of biological particles of the sampler to be tested on the gas circuit. Where, Sref-eff

---the survival rate of microbial of the reference standard sampler; Nref-vc

---the number of biological particles collected by the reference standard sampler; Nref-tot

---the total number of biological particles of the reference standard sampler on the gas circuit.

7.2.6 In accordance with Formula (4), calculate the relative survival efficiency, Sre, namely, the survival rate of microbial: Where, Sre

---the relative survival efficiency; Qi

---each measured value of the airflow ratio of the sampler to be tested, expressed in (L/min); n

---the number of measurements. (see JJF 1826-2020, 7.2)

7.4 Air-tightness of Gas Circuit

7.4.1 Connect the vacuum manometer and a three-way valve to the air inlet of the sampler to be tested; turn on the sampler to be tested and slowly close the air inlet of the three-way valve. When the vacuum manometer indicates an increase of more than 5 kPa, turn off the power of the sampler; simultaneously, completely close the air inlet of the three-way valve and promptly clamp the inlet air pipe of the suction pump. At 1 min, record the reading (F) of the vacuum manometer; calculate the pressure variation , expressed in kPa.

7.4.2 If the sampler is a multi-channel sampling gas circuit, then, the air-tightness of each gas circuit shall be respectively inspected.

f) When a relevant national department puts forward a request for type inspection.

8.3.2 In accordance with Table 1, conduct the type inspection. When one of the inspection items fails to comply with the requirements, then, the sampler shall be determined as disqualified in the type inspection.

8.4 Maintenance Inspection In accordance with Table 1, conduct maintenance inspection at least once a year. When the sampler has its parts replaced or repaired, the maintenance inspection shall be conducted. When one of the inspection items fails to comply with the requirements, then, the sampler shall be determined as disqualified in the maintenance inspection.

9.1 Marking

9.1.1 The marking of the instrument shall include the following contents:

a) Manufacturer's name;

b) Instrument model;

c) Instrument name;

e) Date of manufacture;

f) Exit-factory No.

9.1.2 The nominal values shall include the following contents:

a) Sampling airflow ratio;

b) Sampling efficiency;

c) Survival rate of microbial;

d) Particle size range of sampled particles.

9.2 Packaging

9.2.1 The instrument packaging shall be moisture-proof and shock-proof.

9.2.2 The accompanying documents of the instrument shall include: