BS EN 939:2009 pdf free download – Chemicals used for treatment of water intended for human consumption一 Hydrochloric acid.
B.1 Rules for safe handling and use
The supplier shall provide current safety instructions.
B.2 Emergency procedures
B.2.1 First aid
In case of contact with the skin, remove victim form source of contamination. Promptly flush contaminated skin with water. Promptly remove clothing if soaked through and flush skin with water. Seek medical advice immediately.
In case of contact with the eyes, promptly wash with lots of water while lifting eye lids. Seek medical advice immediately. Continue to rinse.
In case if inhalation, move the exposed person to fresh air at once. Perform artificial respiration if breathing has stopped. Keep affected person warm and at rest. Seek medical advice immediately.
In case of ingestion, never make an unconscious person vomit or drink fluids. Even if conscious do not include vomiting. Seek medical advice immediately. Let victim drink lots of water to dilute chemical.
NOTE The effects can be delayed and the affected person should be kept under observation.
B.2.2 Spillage
Take the following actions with any spillages:
a) wear respiratory equipment and protective clothing;
b) stop any leak if this can be done without any danger. Avoid any contact with the spilt material;
c) neutralize the spilt materials with sodium carbonate or sodium hydrogen carbonate non-combustible or other non-combustible basic chemicals:
d) flush the area with water and then collect it in suitable containers:
e) inform the appropriate authorities if a major spillage occurs.
B.2.3 Fire
Extinguishing media: use extinguisher to suit cause of fire. Hydrochloric acid is non-flammable, but can develop corrosive fumes if heated. Hydrochloric acid reacts with many metals generating hydrogen which forms explosive mixtures with air.
C.1 General principle
Arsenious acid. antimonic acid and selenious acid, the As(IIl), Sb(lll) and Se(IV) oxidation states of arsenic, antimony and selenium, respectively, are instantaneously converted by sodium borohydride reagent in acid solution to their volatile hydrides. The hydrides are purged continuously by argon or nitrogen into an appropriate atomizer of an atomic absorption spectrometer and converted to the gas-phase atoms. The sodium borohydride reducing agent, by rapid generation of the elemental hydrides in an appropriate reaction cell, minimizes dilution of the hydrides by the carrier gas and provides rapid. sensitive determinations of arsenic, antimony and selenium.
The sample is digested to solubilize particulate As, Sb and Se. The digested solutions are treated separately for determination of As, Sb and Se to convert them to As(III), Sb(lll) and Se(IV) oxidation states respectively.
C.2 Interferences
Interferences are minimized because the As. Sb and Se hydrides are removed from the solution containing most potential interfering substances. Slight response variations occur when acid matrices are varied. Control these variations by treating standards and samples in the same manner. Low concentrations of noble metals (approximately 100 .ig/l /l of Ag, Au, Pt, Pd, etc.) concentrations of Cu, Ni and Pb at or greater than 1 mg/I, and concentrations between 0,1 mg/I and 1 mg/I of hydride-forming elements (Bi, Sn and Te) can suppress the response of As, Sb and Se hydrides due to the formation of mixed metal — As-Sb or -Se compounds. The presence of As, Sb and Se in each other’s matrices can cause similar suppression. Reduced nitrogen oxides resulting from HNO3 digestion and nitrite also can suppress instrumental response for all elements. Large concentrations of iodide interfere with the Se determination by reducing Se to its elemental form Do not use any glassware for determining Se that has been used with iodide reduction of As(V).
C.3 Reagents
C.3.1 All reagents shall be of a recognized analytical grade and the water used shall conform to grade 3 in accordance with EN ISO 3696.