Khi> trung khan cap nu'6'c uong
Trong nhung thai ki khung hoang eye diem, cac scr ve sinh dia phuwig co the thuc giyc nguxxi tieu dung ap
dung nhung bien phap can trpng han. Neu thong tin cua cac sa ve sinh dja phipang khac vai 161 khuyen cao a
day, thi phai theo nhCpng khuyen cao cua dja phipang.
Khi thien tai hay nhung hinh thipc khac cua tham hoa lam gian doan viec cung cap nipac gia dung, ban co the
co dipgc mot so lipgng giai han nipac bing each chiet thung pirac nong hay ra nipac da. Trong phan Ian cac
trurceng hop, num; gieng la nguon nueac dueac iea chupng. Neu khong co nifac gidng va phai dung d§n nLcac
song hay nipccc ho, can tranh nhfrng nguon nicoc co vat noi tren mat ntpac hay mau nupac den hoac co mui.
Khi khu> trung khan cap la can thi§t, phai xem xet dieu kien vat li cua mrac. Thu6c tay trung la it hieu nghiem
trong num: van due. Nuac chuan bi de tay trung phai dirge giCp trong thung sach , co day nap kin, va khong bj
ri set.
Thipang co hai phifang phap co the tay trung hieu qua mot sd li/o'ng nho nu'dc. Phu'O'ng phap dlu la dun soi.
Day la phtfang phap tich cue nhat qua do nuac uong difgc an toan do vi trung bj diet. Phu'O'ng phap thuc nhi
la XLP li hoa hoc. Ndu ap dung than trong, mot s6 hoa chat se lam cho phan Ian num: dtpgc khCc nhCpng sinh
vat co hai hay gay benh.
NhOng phu^cyng phap khi> trung khan cap
Dun soi : Dun soi mot phut se tieu diet mpi sinh vat gay benh co trong nipac (a dp cao hccn mot dam so vai
mat mrac bien, dun soi ba phut). Co the cai thien mui nhat nheo cua nLPCcc dun soi sang mrac ti> thung nay
sang thung khac (goi blng thong khi), de ninac tmh trong vong vai gia, hay them vao mot n§m nho mu6i trong
moi lit ripai nupac dun soi.
XIP li hoa hoc : Neu khong dun soi dugc, phai tay triing bang phirang phap hoa hoc. Hai hoa chat
thirong dipgc dung la clo va i6t. Clo va iot co phan hieu qua trong viec phong chdng Giardia, nhu-ng co the
khong hieu qua trong viec kiem soat Cryptosporidium. Ba\ the chf dung clo hay i6t de tay trung nipac
gi^ng (trai voi nhCpng ngudn nipac be mat nhup nipac song, nupac ho, nipac trilu) vi nipac gi§ng it co kha
nang chipa dyng nhCpng benh nay. Clpr thipang co hieu qua han trong viec kiem soat Giardia, va ca hai
loai hoa chat nay phat huy tac dung tot han trong nipac am.
NhCmg phipang phap dung clo
Khu> trung bang clo : khi khong dun soi du>gc, phai tay trung blng hoa chat. Chat tay gia dung thipang co
mot thanh t6 clo tay trung nipac. Cach thi>c si> dung thyang dipgc in tren bao bi. Khi khong co each thicc can
thi6t, tim doc ti phan clo tren nhan hieu va dung thong tin trong bang hipang din dipai day :
Ti phan clo So gipt cho moi lit ripoi nird'C
1% ' 10
4-6% 2
7-10% 1
(n§u khong bi^t tF phan clo, do mipai gigt cho moi lit rimi nipac. Nhan doi lieu lipgng clo d6i vai nipac due,
nipac co mau hay nipac CIPC lanh).
-------
XLP li phai Gueac khuay tron va de yen co nap day trong vong 30 phut. Mirac phai co mot mui clo nhe,
neu khong lap lai lieu lucgng va de nuac yen them 15 phut nfra. Neu nipac XLP li co mui clo qua nang, thi co
the la diu bat bang each de ntpac ngoai khong khi (khong day nip) hay sang mrac nhieu Ian ti> thung sach
nay sang thung sach khac.
Hat Calcium Hypochlorite. Do hem va hoa tan mot muong day hat calcium hypochlorite (xap xf % ounce) CLP
m6i hai gallon num. Hon hgp nay se cho ra mot dung djch clo khoang 500 mg/L, do hat calcium hypochlorite
co ham iLpgng clo len den 70 % trpng luyng cua hat. De tay ue" nLpac, them dung djch clo theo ti le mot phan
dung djch clo cho moi 100 phan niraccan XLP li. Oieu nay xapxi vai viecthem 1 pint (16 oz) clo CLP mai 12.5
gallon nueac dLpgc tay trung. De loai tn> mui clo, thong khi nLpac nhu1 dLpgc mo ta a tren.
Clorine Tablets (vien clo). Co the mua nhCpng vien clo voi lieu ILpgng can thi§t cho viec khCp trung nLPcrc u6ng
tai cac cCpa hang du>gc pham va hang the thao. SLP dung chung nhu dLpgc ch? dan. Neu khong co bang chf
d§n, dung mot vien cho m6i lit nra\ nLpac can lam tinh khiet.
Thudc iot (tincture of iodine)
Co the dung clo gia dung trong tui cap CLPU de khCp trung nLPcrc. Do nam gipt cua thuoc i6t 2 % United States
Pharmacopeia (U.S.P) vao moi lit ruai nLpac trong. Doi vai nLpac due, do mLPol gipt va de dung djch yen it nhat
30 phut.
Vien iot (iodine tablet)
Co the mua nhfrng vien i6t sin chCca lieu ILpgng can thiet de khCp trung nuac trong cac cCpa hang dLPp-c
pham va cCpa hang the thao. SLP dung chung nhu1 dLpgc chi dan. Neu kh6ng co bang chi dan, dung mot
vien cho moi lit ami nirac can lam tinh khiet.
NITOC DUNG O^ U6NG, NAU NlfCXNG, CH^ BI^N BAT Cl>D6 U6NG SAN NAO, HOAC DANH
RANG NEN OU'aC KHU1 TRUNG DUNG QUY TRJNH.
Van phong Nuac 4606-M EPA 816-F-05-024 Thang 9 nam 2005 www.epa.gov/safcwatcr
------- |