The second lab managers’ meeting of the South-East Asia Laboratory NETwork (SEALNET) took place on 19 - 23 November 2018 in ICAR-IISS (Indian Institute of Soil Science), Bhopal, India. Mr. Phai Đỗ Duy, Central Analytical Laboratory - Soils and Fertilizers Research Institute, Vietnam (2nd Day)

1. Internal quality control
Central Analytical Laboratory –
Soils and Fertilizers Research Institute

2. - 01 Doctor, 04 Masters, 03 Engineers
Human resources

3. 5. Photos of your equipment
For example:
Balances, ovens, fumehoods, shakers
Spectrophotometer
Kjeldahl digester
Show also any ‘automated’ equipment you
have such as Auto Analyzers etc. (if any)
[The aim of these photos is to give an overview of
what equipment you have in your lab]
Flame photometer or AAS
ANALYSIS INSTRUMENTS

5. Document system of Central Analytical Laboratory
QUALITY MANAGEMENT SYSTEM OF
CENTRAL ANALYTICAL LABORATORY

6. Soil:
pHH2O&Kcl, total N, Total P,
Total K, avail P, avail K,
OM, Cu, Zn, Pb, Cd, As
Cr.
Fertilizer:
Humidity, total N,
effective N, effective P,
effective K, OM, S, Ca,
Mg, Fe, Mo, Mn, Cu, Zn,
Pb, Cd, As.
Water:
pH, As
Plant:
Pb, Cd
ISO/IEC 17025:2005 certification

7. Do you have and use an internal quality control
system
We have internal control system
• Balance: F2 set of weights 1g; 5g; 200g
• Nitrogen distill equipment (Kjeldahl UDK 129): Before
sampling, Kjeldhal equipment was inspected by storing 14 ml
of standard ammonium 0.05 mg N / ml with alkali. Titrate 5ml
± 0.1 ml of 0.01 N HCl standard solution to the required level.
If the titration volume is less than 5ml then the distillation
device opens, if the titration volume is larger than 5ml then
possible due to alkaline contamination from storage tanks or
from unclean equipment and the equipment should be
overcome.
• Test sample: Internal reference sample

8. Internal reference sample
F2 sets of weights
Kjeldahl UDK 129

9. What are the characteristics of the material
used for quality control (QC)?
What kind of material is used to perform the quality control?
- Natural soils? YES
- Synthetic material? NO
- Chemicals? YES
Is the material used for QC:
- prepared by yourself ? YES
- prepared out of the laboratory ? No
- bought to a company as a certified reference material ?
NO

10. Sample collection Processing Sample mix
Portion preservation Equal evaluation
Compare result from ASPAC reference
sample using.
Preparation internal soil reference

12. Compared internal sample results between SFRI and ASPAC
before using as internal control
Soil reference sample
Element Statitist Result of SFRI
Median result of ASPAC
(n labs)
Comparison of
results between
SFRI and ASPAC
No. Reps 10
pHH2O Mean 7.962 8.04 (37) Acceptable
SD 0.017
CV% 0.212
No. Reps 20
OC (%) Mean 0.459 0.44% (33) Acceptable
SD 0.010
CV% 2.183
No. Reps 20
Total N (%) Mean 0.064 0.064% (39) Acceptable
SD 0.003
CV% 4.312
No. Reps 20
Total Mean 0.090 P 0.036% (22) Acceptable
P2O5 (%) SD 0.002 P2O5 0.08%
CV% 2.073
No. Reps 20
Bray-2 P
Mean 33.93
No corresponding data
but
Acceptable
(mg/kg) SD 0.017 Bray-1 is 1.4 mg P/kg (8)
CV% 0.494 or 3.2 mg P2O5/kg
No. Reps 18
Available K Mean 4.243 Exch K (cmol/kg) 0.10 Acceptable
as K2O SD 0.040 (33) 4.7 mg K2O/100 g
(mg/100 g) CV% 0.949

13. Analysis of the control material
Are you using the control material for all your analytical parameters? NO
If 'NO' are you using it for:
- pH YES
- EC YES
- Carbon YES
- Total N YES
- Total P YES
- Total K YES
- Available P YES
- Available K YES
How often do you analyze your control material?
- in every analytical batch YES/NO

14. Analysis of the control material
How often do you analyze your control material?
- in every analytical batch YES

15. Comparison of control material results to
specific statistical limits

16. Action after a negative results for quality
control
If the quality control procedure indicates a failure (results out the statistical
limits), what do you do?
CHECK:
+ Analysis equipment
+ Chemical: Reagent, standard solution…
+ Environmental condition: Temperature, contamination….
+ Balance, recording ….
+ SOP

17. Staff qualification
Is there a quality control officer to look into the quality of the results?
NO

18. Examples coming from my lab

19. Examples coming from my lab

20. Thanks for your attention