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radiello® Diffusive Air Sampler Calibration Solutions & Kits

Calibration Solution for H2S

Product No. RAD171

RAD171 relieves you from the task of preparing the sodium sulfide standard solution for the calibration curve used for the determination of H2S by the cartridge RAD170.

Since sodium sulfide is deliquescent, its weight is not a primary standard and sodium sulfide solution need titration once prepared. Moreover, titration must be repeated often due to the instability of diluted solution (one hour time is sufficient to decrease sulfide content by 10%).

RAD171 is a methylene blue concentrated solution that, once diluted 1:50, provides the same absorbance value at 665 nm of a sodium sulfide solution of with concentration 1.145 μg·ml-1 sulfide ions. This concentration value has been chosen to obtain the highest absorbance value within the linearity range of the spectrophotometer.

To obtain a complete calibration curve, just dilute the mother solution as shown in the table.

Solution ml of ml of water equivalent to μg·ml-1 of S2-
A 2 of RAD171 98 1.145
B 25 of A 25 0.572
C 10 of A 40 0.229
D 5 of A 45 0.115


RAD171 contains 100mL solution that allows you to prepare as many as 50 calibration curves. Kept closed at room temperature, code 171 solution is stable for at least one year.

Calibration Solution for Aldehydes

Product No. RAD302

Calibration curves for aldehydes are obtained with standard solutions of the corresponding 2,4-dinitrophenylhydrazones. Although their synthesis is straightforward, their purification is tricky and time-consuming.

RAD302 offers a certified and convenient choice: a solution of nine 2,4-dinitrophenylhydrazones in a solvent compatible with HPLC eluents and with concentrations suitable for the preparation of calibration curves in the range usually spanned by radiello samples.

RAD302 is delivered as 10 ml of acetonitrile solution of the nine 2,4-dinitrophenylhydrazones formed by the aldehydes listed in the table, contained in a pierceable-septum crimped cap vial. The listed concentration values are indicative, actual ones are certified for each lot.

2,4-DNPH of μg·ml-1 as aldehyde 2,4-DNPH of μg·ml-1 as aldehyde
formaldehyde 50 isopentanal 50
acetaldehyde 50 pentanal 50
acrolein 10 hexanal 50
propanal 50 benzaldehyde 50
butanal 50    

Kept tightly capped in a dark place at 4 °C, the solution is stable for at least four months.

Calibration Kit for BTEX (CS2 desorption)

Product No. RAD405

This calibration kit has been conceived for the analysis of BTEX sampled in urban environments by the cartridge RAD130 and chemically desorbed by carbon disulfide.

The kit may be used both for routine calibration and for scheduled quality control of the calibration procedure described above.

It is composed of 12 RAD130 cartridges, three of which are blanks and nine, divided into three groups of three, preloaded with BTEX to simulate 7 days exposures (10,080 minutes) to the concentrations listed in the table. The values shown are indicative, actual ones are certified for each lot.

 

RAD405 Simulated Concentrations in μg·m-3
(7 days exposure equivalent)
Group 1 Group 2 Group 3
benzene 1 10 50
toluene 2 20 100
ethylbenzene 1 10 50
m-xylene 1 10 50
p-xylene 1 10 50
o-xylene 1 10 50

The mass of each analyte deposited onto the cartridge spans the whole range of concentrations usually found in urban environments, extreme values included. BTEX loading is performed by injection of precisely known amounts of vaporized standard solutions in CS2 of the five compounds under nitrogen flow.

Kept at 4 °C, the cartridges are stable for at least four months.

Calibration Kit for VOCs in Workplace Environments

Product No. RAD406

This kit has been conceived for scheduled quality control of the calibration procedure for the analysis of volatile organic compounds (VOCs) sampled by RAD130 cartridges in workplace environments.

It is composed of 12 RAD130 cartridges, three of which are blanks and nine, divided into three groups of three, preloaded with VOCs to simulate 8 hours exposures (480 minutes) to the concentrations listed in the table. The values shown are indicative, actual ones are certified for each lot.

 

RAD406 Simulated Concentrations in μg·m-3
(8 days exposure equivalent)
Group 1 Group 2 Group 3
benzene 0.1 0.2 0.4
toluene 19 38 76
ethylbenzene 12 24 48
m-xylene 12 24 48
p-xylene 12 24 48
o-xylene 12 24 48
butanol 15 30 60
2-etoxyiethyl acetate 2.5 5 10

The composition of the mixture is simple but it includes compounds with different polarity. The loaded mass is calculated in order to represent exposures to 0.5, 1 and 2 times the TLV value for the mixture. VOCs loading is performed by injection of precisely known amounts of calibrated mixtures of the eight compounds under nitrogen flow.

Kept at 4 °C, the cartridges are stable for at least four months.

Calibration Kit for BTEX (thermal desorption)

Product No. RAD407

This calibration kit has been conceived for the analysis of BTEX sampled in urban environments by the cartridge RAD145 and thermally desorbed.

The kit may be used both for routine calibration and for scheduled quality control of the calibration procedure described on page E5.

It is composed of 12 RAD145 cartridges, three of which are blanks and nin, divided into three groups of three, preloaded with BTEX to simulate 7 days exposures (10,080 minutes) to the concentrations listed in the table. The values shown are indicative, actual ones are certified for each lot.

 

RAD407 Simulated Concentrations in μg·m-3
(7 days exposure equivalent)
Group 1 Group 2 Group 3
benzene 1 10 25
toluene 2 20 50
ethylbenzene 1 10 25
m-xylene 1 10 25
p-xylene 1 10 25
o-xylene 1 10 25

BTEX loading is performed by injection of precisely known amounts of vaporized standard solutions in methanol of the five compounds under nitrogen flow. During the analysis the chromatographic peak of methanol will be visible.

Kept at 4 °C, the cartridges are stable for at least four months.

Materials

     
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