To check water samples preservation and volumes as the following. NOM-230-SSA1-2002.
|DETERMINATION||PACKAGING MATERIAL||MINIMUM VOLUME (mL)||PRESERVATION||MAXIMUM STORAGE TIME|
|Cyanides||p, v||1000||Add NaOH to pH> 12; cooling from 4 to 10 ° C and keep out of the light||24 hours|
|Chlorine residual p, v||p, v||50||Analyze immediately|
|Chlorides||p, v||200||Refrigerate 4 to 10 ° C and keep out of the light||48 hours|
|Color||p, v||500||Refrigerate 4 to 10 ° C and keep out of the light||48 horahourss|
|Total hardness||p, v||100||Add HNO3 or H2SO4 to pH<2 (*)||14 days|
|Phenols||p, v PTFE||500||Add H2SO4 to pH <2 and cool to 4-10 ° C||Analyze as soon as possible|
|Fluorides||P||500||Refrigerate 4 to 10°C||28 days|
|Aromatic hydrocarbons (BTEX)||S||25||Refrigerate 4 to 10 ° C and keep out of the light||7 days|
|Metals in general||p, v (A)||1000||Add 1 mL of concentrated nitric acid per 100 mL of sample.||180 days
Only mercury determination stored up 4 weeks
|Nitrates||p, v||100||Refrigerate 4 to 10 ° C keep out of the light||48 hours|
|Nitrites||p, v||100||Refrigerate 4 to 10 ° C keep out of the light|
|Ammoniacal nitrogen||p, v||500||Add H2SO4 to pH <2 and refrigerate 4 to 10 ° C||7 days|
|Odor||V||500||Analyze smell as soon as possible. Refrigerate||6 hours|
|pH||p, v||50||Analyze immediately|
|Pesticides||s||1000||Refrigerate 4 to 10 ° C||7 days
pesticides extracted with solvents maximum storage time is 40 days
|Alpha radioactivity overall||p,v||1000||Add HCl or HNO3 to pH<2||180 days|
|Gross beta radioactivity||p,v||1000||Add HCl or HNO3 to pH<2||180 days|
|Solid||p, v||200||Refrigerate 4 to 10 ° C and keep out of the light||7 days|
|Sodium||p, v||100||Refrigerate 4 to 10 ° C and keep out of the light||18 days|
|Sulfates||p, v||100||Refrigerate 4 to 10 ° C and keep out of the light||28 days|
|Methylene blue active substances||p, v||250||Refrigerate 4 to 10 ° C and keep out of the light||48 hours|
|Temperature||p, v||Determine immediately|
|Trihalomethanes||S||25||Refrigerate 4 to 10 ° C and keep out of the light||7 days|
|Turbidity||p, v||100||Refrigerate 4 to 10 ° C and keep out of the light||24 hours|
|Iodine||v (amber)||50||Analyze immediately|
* Skip the preservation if the sample is analyzed immediately.
p - plastic
p (A) - rinsed with HNO3 1 + 1
pH - hydrogen potential
s - glass rinsed with organic solvents; inside the lid of the container coated with Teflon
v - glass
v (A) - rinsed with HNO3 1 + 1
PTFE - polytetrafluoroethylene cap
BTEX - benzene, toluene, ethylbenzene, xylene
1. For the sample is not enough, in the determination of residual chlorine, nitrates, ammonia nitrogen, solid pH, methylene blue active, turbidity and iodine substances, it is recommended that the minimum volume multiplied by 4 so that the laboratory has the ability to perform if necessary, a repeat.
2. The preservation of the sample in the determination of total hardness, is exclusively for contaminated and waste water; as in natural waters is not necessary to add acid as preservative.
Food preservation conditions set out in paragraph 5.5 Storage and Transport of the procedure P-MU-002 are checked.
5.5 Storage and Transport
126.96.36.199 The handling and transport of samples must be made so that its rupture, disruption or contamination is prevented by avoiding exposure to direct sunlight.
188.8.131.52 Samples must be delivered to the laboratory as quickly as possible. Perishable food must be transported under temperature of 2-8 ° C; and kept at that temperature until the time of analysis, which should be started within 24 hours of collection. If frozen foods, the temperature should not exceed 0 ° C using dry ice to preserve it. For cooling is advisable to use containers with coolant or drinking ice contained in waterproof plastic bags to prevent melt water reaches the top of the packaging or in any way contaminate food sampled.
184.108.40.206 For soft individual samples, preventing the pressure which may have other containers or an excessive amount of them, the deform or give rise to spills and cause the contents to contact the outside of the envelope.
220.127.116.11 In the case of non-perishable samples, prevent damage, damp or contaminated with others.
18.104.22.168 Products with commercial form must be transported in their original containers at room temperature, provided it does not exceed 45 ° C.
22.214.171.124 For the conservation, during transport of the samples is not allowed the use of chemicals.
For other cases the minimum to receive amounts for analysis the following criteria for acceptance and rejection will be taken.
|Sample Type||Area||Parameter||Minimum Quantity||Temperature|
|Water and other foods||MB||Total coliforms||120 g or mL||Commercial presentation products (non-perishable) be transported in their original containers at room temperature, provided it does not exceed 45 ° C.|
|Yeasts and molds|
|Food and other||FQ||Dietetics||250 g or mL||Products with (non-perishable) commercial presentation must be transported in their original containers at room temperature, provided it does not exceed 45 ° C.|
|Concrete water||FQ||GyA, SST, carbonates, bicarbonates, sulfates, chlorides, BOD, TDS, total alkali, carbon dioxide||2L||Preserved in ice or refrigeration|
|Soil||FQ||pH, moisture, MO, texture, phosphorus, cation exchange, micro and macro nutrients, pollutants, total nitrogen, salinity, etc.||1 kg 500 g wet sample or if the sample is dry||N/A|
|Bio-solids and sludge||MB||Total and fecal coliforms, Salmonella, helminth eggs, Heavy metals||1 kg||N/A|
When samples do not meet the acceptance criteria (but are amenable to analysis) are discussed only with prior authorization of the customer and the Technical Management. The reasons are settled and authorization format F-CA-029. In point delivered.
For any question contact the staff ECOLABORATORIOS, SA DE C.V.
We have the ability to develop methods and techniques according to customer needs.