{"id":2807,"date":"2026-06-18T16:43:47","date_gmt":"2026-06-18T16:43:47","guid":{"rendered":"https:\/\/huyuglobal.com\/?p=2807"},"modified":"2026-06-18T16:43:49","modified_gmt":"2026-06-18T16:43:49","slug":"dimensions-of-an-electrical-box","status":"publish","type":"post","link":"https:\/\/huyuglobal.com\/vi\/blog\/dimensions-of-an-electrical-box\/","title":{"rendered":"K\u00edch th\u01b0\u1edbc c\u1ee7a m\u1ed9t h\u1ed9p \u0111i\u1ec7n"},"content":{"rendered":"

M\u1ed9t th\u1ee3 \u0111i\u1ec7n l\u00e0m vi\u1ec7c tr\u00ean m\u1ed9t d\u1ef1 \u00e1n c\u1ea3i t\u1ea1o kh\u00e1ch s\u1ea1n g\u1ea7n \u0111\u00e2y \u0111\u00e3 c\u00f3 tr\u1ea3i nghi\u1ec7m th\u00fa v\u1ecb khi c\u1ed1 g\u1eafng nh\u00e9t m\u1ed9t m\u1edb d\u00e2y r\u1ed1i v\u00e0o m\u1ed9t h\u1ed9p n\u1ed1i sau khi m\u1edf n\u00f3 ra. H\u1ed9p n\u1ed1i l\u00e0 m\u1ed9t h\u1ed9p vu\u00f4ng 4\u2033 th\u00f4ng th\u01b0\u1eddng v\u1edbi \u0111\u1ed9 s\u00e2u 1.25\u2033, th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng v\u1edbi m\u1ed9t m\u1ea1ch \u0111\u01a1n. Tuy nhi\u00ean, h\u1ed9p n\u00e0y ch\u1ee9a b\u1ed1n m\u1ea1ch! Ba m\u1ea1ch b\u1ed5 sung \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00e9o v\u00e0o h\u1ed9p theo th\u1eddi gian, \u0111\u1ec3 l\u1ea1i t\u1ed5ng c\u1ed9ng b\u1ea3y d\u00e2y d\u1eabn trong h\u1ed9p, g\u1ea7n g\u1ea5p \u0111\u00f4i s\u1ed1 l\u01b0\u1ee3ng d\u00e2y d\u1eabn t\u1ed1i \u0111a cho ph\u00e9p trong lo\u1ea1i h\u1ed9p n\u1ed1i n\u00e0y! N\u1eafp h\u1ed9p h\u1ea7u nh\u01b0 kh\u00f4ng v\u1eeba v\u1edbi h\u1ed9p n\u1ed1i. M\u1ed9t trong nh\u1eefng l\u00fd do l\u1edbn nh\u1ea5t khi\u1ebfn \u0111i\u1ec1u n\u00e0y x\u1ea3y ra l\u00e0 s\u1ef1 thi\u1ebfu hi\u1ec3u bi\u1ebft ho\u00e0n to\u00e0n v\u1ec1 c\u00e1ch m\u00e0 k\u00edch th\u01b0\u1edbc (v\u00ed d\u1ee5: chi\u1ec1u r\u1ed9ng, chi\u1ec1u cao v\u00e0 \u0111\u1ed9 s\u00e2u) c\u1ee7a c\u00e1c h\u1ed9p \u0111i\u1ec7n \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh v\u00e0 t\u1ea7m quan tr\u1ecdng c\u1ee7a ch\u00fang. C\u00e1c h\u1ed9p \u0111i\u1ec7n kh\u00f4ng ch\u1ec9 l\u00e0 nh\u1eefng c\u00e1i ch\u1ee9a \u0111\u1ec3 n\u1ed1i d\u00e2y. Th\u1ec3 t\u00edch, h\u00ecnh d\u1ea1ng v\u00e0 \u0111\u1ed9 s\u00e2u c\u1ee7a m\u1ed9t h\u1ed9p \u0111\u1ec1u \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn th\u1eddi gian m\u00e0 m\u1ed9t k\u1ebft n\u1ed1i s\u1ebd t\u1ed3n t\u1ea1i, c\u0169ng nh\u01b0 l\u01b0\u1ee3ng nhi\u1ec7t s\u1ebd t\u1ecfa ra t\u1eeb k\u1ebft n\u1ed1i.<\/p>\n

\"T\u1ea1i<\/p>\n

T\u1ea1i sao K\u00edch Th\u01b0\u1edbc H\u1ed9p \u0110i\u1ec7n L\u00e0 Y\u00eau C\u1ea7u An To\u00e0n, Kh\u00f4ng Ph\u1ea3i S\u1edf Th\u00edch<\/h2>\n

Theo B\u1ed9 lu\u1eadt \u0110i\u1ec7n Qu\u1ed1c gia (NEC) \u0110i\u1ec1u 314, c\u00f3 gi\u1edbi h\u1ea1n v\u1ec1 s\u1ed1 l\u01b0\u1ee3ng d\u00e2y d\u1eabn c\u00f3 th\u1ec3 v\u1eeba b\u00ean trong m\u1ed9t h\u1ed9p d\u1ef1a tr\u00ean k\u00edch th\u01b0\u1edbc c\u1ee7a h\u1ed9p. Khi t\u00ednh to\u00e1n h\u1ed9p c\u1ee7a b\u1ea1n, b\u1ea1n ph\u1ea3i t\u00ednh \u0111\u1ebfn c\u00e1c m\u1ee5c sau: m\u1ed7i d\u00e2y (kh\u00f4ng c\u00e1ch \u0111i\u1ec7n ho\u1eb7c tr\u1ea7n), m\u1ed7i k\u1eb9p s\u1ebd g\u1eafn v\u00e0o d\u00e2y, b\u1ea5t k\u1ef3 thi\u1ebft b\u1ecb n\u00e0o s\u1ebd \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t, v\u00e0 b\u1ea5t k\u1ef3 ph\u1ee5 ki\u1ec7n n\u00e0o kh\u00e1c s\u1ebd \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t. N\u1ebfu b\u1ea1n c\u00f3 m\u1ed9t h\u1ed9p qu\u00e1 nh\u1ecf \u0111\u1ec3 ch\u1ee9a s\u1ed1 l\u01b0\u1ee3ng d\u00e2y d\u1eabn; n\u00f3 s\u1ebd t\u1ea1o \u00e1p l\u1ef1c l\u00ean c\u00e1c d\u00e2y d\u1eabn v\u00e0 c\u1ea3n tr\u1edf vi\u1ec7c t\u1ecfa nhi\u1ec7t, g\u00e2y ra s\u1ef1 c\u1ed1 c\u00e1ch \u0111i\u1ec7n khi thi\u1ebft b\u1ecb \u0111\u01b0\u1ee3c \u0111\u1ea9y v\u00e0o v\u1ecb tr\u00ed. NEC \u0111\u00e3 \u0111\u1eb7t ra y\u00eau c\u1ea7u v\u1ec1 k\u00edch th\u01b0\u1edbc t\u1ed1i thi\u1ec3u cho c\u00e1c h\u1ed9p; do \u0111\u00f3, n\u1ebfu b\u1ea1n s\u1eed d\u1ee5ng h\u1ed9p c\u00f3 k\u00edch th\u01b0\u1edbc t\u1ed1i thi\u1ec3u, b\u1ea1n s\u1ebd an to\u00e0n kh\u1ecfi v\u1ea5n \u0111\u1ec1 n\u00e0y. NEC ch\u1ec9 \u0111\u1ecbnh m\u1ed9t m\u1ee9c th\u1ec3 t\u00edch cho m\u1ed7i d\u00e2y d\u1eabn c\u00e1ch \u0111i\u1ec7n d\u1ef1a tr\u00ean k\u00edch th\u01b0\u1edbc c\u1ee7a n\u00f3 (14 AWG = 2.0 inch kh\u1ed1i, 12 AWG = 2.25 inch kh\u1ed1i, 10 AWG = 2.5 inch kh\u1ed1i) \u0111\u1ec3 cho ph\u00e9p c\u00e1c m\u1ee5c b\u1ed5 sung m\u00e0 b\u1ea1n c\u00f3 b\u00ean trong h\u1ed9p c\u1ee7a b\u1ea1n. V\u00ed d\u1ee5, khi th\u1ef1c hi\u1ec7n t\u00ednh to\u00e1n \u0111\u1ea7y \u0111\u1ee7 th\u1ec3 t\u00edch h\u1ed9p c\u1ee7a b\u1ea1n, b\u1ea1n s\u1ebd c\u1ea7n bao g\u1ed3m c\u00e1c d\u00e2y n\u1ed1i \u0111\u1ea5t, c\u00e1c k\u1eb9p b\u00ean trong, b\u1ea5t k\u1ef3 \u0111\u1ea7u n\u1ed1i c\u00e1p n\u00e0o, v\u00e0 thi\u1ebft b\u1ecb s\u1ebd \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t b\u00ean trong h\u1ed9p. M\u1ed9t \u1ed5 c\u1eafm ho\u1eb7c yoke c\u00f4ng t\u1eafc \u0111\u01a1n s\u1ebd \u0111\u01b0\u1ee3c t\u00ednh b\u1eb1ng hai d\u00e2y d\u1eabn cho m\u1ee5c \u0111\u00edch t\u00ednh to\u00e1n n\u00e0y.<\/p>\n

T\u1ed5ng s\u1ed1 k\u1ebft qu\u1ea3 x\u00e1c \u0111\u1ecbnh th\u1ec3 t\u00edch h\u1ed9p t\u1ed1i thi\u1ec3u c\u1ea7n thi\u1ebft. T\u00e0i nguy\u00ean t\u1eeb Hi\u1ec7p h\u1ed9i B\u1ea3o v\u1ec7 Ch\u00e1y Qu\u1ed1c gia (NFPA)<\/a> v\u00e0 c\u00e1c \u1ea5n ph\u1ea9m th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed nh\u01b0 EC&M<\/a> cung c\u1ea5p c\u00e1c v\u00ed d\u1ee5 chi ti\u1ebft v\u1ec1 th\u1ec3 t\u00edch h\u1ed9p.<\/p>\n

\u0110\u1ec3 c\u00f3 c\u00e1i nh\u00ecn c\u1ee5 th\u1ec3 h\u01a1n v\u1ec1 c\u00e1c thi\u1ebft b\u1ecb ph\u00f9 h\u1ee3p v\u1edbi nh\u1eefng v\u1ecf n\u00e0y, h\u01b0\u1edbng d\u1eabn c\u1ee7a ch\u00fang t\u00f4i v\u1ec1 k\u00edch th\u01b0\u1edbc c\u1ea7u dao b\u1ea1n c\u1ea7n<\/a> gi\u1ea3i th\u00edch v\u1ec1 b\u1ea3o v\u1ec7 qu\u00e1 d\u00f2ng m\u00e0 b\u1ea3ng m\u1ea1ch c\u1ea7u dao \u2014 b\u1ea3n th\u00e2n n\u00f3 l\u00e0 m\u1ed9t h\u1ed9p \u0111i\u1ec7n r\u1ea5t l\u1edbn \u2014 ph\u1ea3i cung c\u1ea5p. V\u00e0 \u0111\u1ec3 hi\u1ec3u v\u1ec1 c\u00e1c thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 \u0111\u01b0\u1ee3c ch\u1ee9a trong nhi\u1ec1u v\u1ecf, b\u00e0i vi\u1ebft c\u1ee7a ch\u00fang t\u00f4i v\u1ec1 c\u00e1c c\u1ea7u dao UL 489<\/a> gi\u1ea3i th\u00edch khung ch\u1ee9ng nh\u1eadn \u0111i\u1ec1u ch\u1ec9nh c\u00e1c c\u1ea7u dao \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t trong b\u1ea3ng \u0111i\u1ec1u khi\u1ec3n v\u00e0 trung t\u00e2m t\u1ea3i.<\/p>\n

\"C\u00e1c<\/p>\n

C\u00e1c Lo\u1ea1i H\u1ed9p \u0110i\u1ec7n Th\u00f4ng D\u1ee5ng v\u00e0 K\u00edch Th\u01b0\u1edbc \u0110i\u1ec3n H\u00ecnh C\u1ee7a Ch\u00fang<\/h2>\n

Kh\u00f4ng ph\u1ea3i t\u1ea5t c\u1ea3 c\u00e1c h\u1ed9p \u0111i\u1ec7n<\/strong> c\u00f3 th\u1ec3 thay th\u1ebf cho nhau. Lo\u1ea1i h\u1ed9p x\u00e1c \u0111\u1ecbnh n\u01a1i n\u00f3 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t \u2014 trong t\u01b0\u1eddng, tr\u00ean b\u1ec1 m\u1eb7t, ngo\u00e0i tr\u1eddi \u2014 v\u00e0 nh\u1eefng g\u00ec n\u00f3 c\u00f3 th\u1ec3 ch\u1ee9a. B\u1ea3ng sau t\u00f3m t\u1eaft b\u1ed1n lo\u1ea1i h\u1ed9p ph\u1ed5 bi\u1ebfn nh\u1ea5t v\u00e0 k\u00edch th\u01b0\u1edbc m\u00e0 b\u1ea1n s\u1ebd th\u01b0\u1eddng g\u1eb7p tr\u00ean k\u1ec7 c\u1ee7a nh\u00e0 cung c\u1ea5p.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
Lo\u1ea1i H\u1ed9p<\/th>\nK\u00edch th\u01b0\u1edbc Th\u00f4ng th\u01b0\u1eddng (R\u1ed9ng \u00d7 Cao \u00d7 S\u00e2u)<\/th>\nTh\u1ec3 t\u00edch Th\u00f4ng th\u01b0\u1eddng (Inch Kh\u1ed1i)<\/th>\nS\u1eed d\u1ee5ng Ph\u1ed5 bi\u1ebfn<\/th>\n<\/tr>\n<\/thead>\n
H\u1ed9p Thi\u1ebft B\u1ecb Nh\u1ef1a ho\u1eb7c Kim Lo\u1ea1i \u0110\u01a1n<\/strong><\/td>\n3\u2033 \u00d7 2\u2033 \u00d7 2\u20111\/2\u2033 \u0111\u1ebfn 3\u20111\/2\u2033 s\u00e2u<\/td>\n12\u201322 in\u00b3.<\/td>\nM\u1ed9t c\u00f4ng t\u1eafc ho\u1eb7c m\u1ed9t \u1ed5 c\u1eafm \u0111\u00f4i<\/td>\n<\/tr>\n
H\u1ed9p Thi\u1ebft B\u1ecb \u0110\u00f4i<\/strong><\/td>\n3\u2033 \u00d7 4\u20111\/2\u2033 \u00d7 2\u20111\/2\u2033 \u0111\u1ebfn 3\u20111\/2\u2033 s\u00e2u<\/td>\n25\u201340 in\u00b3.<\/td>\nHai c\u00f4ng t\u1eafc ho\u1eb7c hai \u1ed5 c\u1eafm c\u1ea1nh nhau<\/td>\n<\/tr>\n
H\u1ed9p Kim Lo\u1ea1i Vu\u00f4ng 4 Inch<\/strong><\/td>\n4\u2033 \u00d7 4\u2033 \u00d7 1\u20111\/4\u2033, 1\u20111\/2\u2033, ho\u1eb7c 2\u20111\/8\u2033 s\u00e2u<\/td>\n18\u201330 cu. in. (c\u00e1c phi\u00ean b\u1ea3n s\u00e2u h\u01a1n ch\u1ee9a nhi\u1ec1u h\u01a1n)<\/td>\nH\u1ed9p n\u1ed1i, ho\u1eb7c h\u1ed9p thi\u1ebft b\u1ecb v\u1edbi v\u00f2ng th\u1ea1ch cao<\/td>\n<\/tr>\n
H\u1ed9p Kim Lo\u1ea1i Vu\u00f4ng 4\u201111\/16\u2033<\/strong><\/td>\n4\u201111\/16\u2033 \u00d7 4\u201111\/16\u2033 \u00d7 1\u20111\/2\u2033 \u0111\u1ebfn 2\u20111\/8\u2033 s\u00e2u<\/td>\n29\u201350 in\u00b3.<\/td>\nH\u1ed9p n\u1ed1i l\u1edbn h\u01a1n, nhi\u1ec1u m\u1ed1i n\u1ed1i, \u1ee9ng d\u1ee5ng th\u01b0\u01a1ng m\u1ea1i<\/td>\n<\/tr>\n
H\u1ed9p B\u00e1t Gi\u00e1c (H\u1ed9p Tr\u1ea7n)<\/strong><\/td>\n\u0110\u01b0\u1eddng k\u00ednh 4\u2033 \u00d7 1\u20111\/2\u2033 ho\u1eb7c 2\u20111\/8\u2033 s\u00e2u<\/td>\n15\u201322 in\u00b3.<\/td>\n\u0110\u00e8n chi\u1ebfu s\u00e1ng tr\u1ea7n, c\u1ea3m bi\u1ebfn kh\u00f3i<\/td>\n<\/tr>\n
H\u1ed9p Ti\u1ec7n L\u1ee3i (H\u1ed9p L\u1eafp B\u1ec1 M\u1eb7t)<\/strong><\/td>\n4\u2033 \u00d7 2\u2033 \u00d7 1\u20111\/2\u2033 \u0111\u1ebfn 2\u2033 s\u00e2u<\/td>\n8\u201314 in\u00b3.<\/td>\nC\u00f4ng t\u1eafc ho\u1eb7c \u1ed5 c\u1eafm l\u1eafp b\u1ec1 m\u1eb7t trong gara, t\u1ea7ng h\u1ea7m<\/td>\n<\/tr>\n
H\u1ed9p Ch\u1ed1ng Th\u1eddi Ti\u1ebft (Ngo\u00e0i Tr\u1eddi)<\/strong><\/td>\n\u0110\u01a1n gang: ~3\u2033 \u00d7 5\u2033 \u00d7 2\u2033 s\u00e2u<\/td>\n15\u201325 in\u00b3.<\/td>\n\u1ed4 c\u1eafm v\u00e0 c\u00f4ng t\u1eafc ngo\u00e0i tr\u1eddi, v\u1edbi n\u1eafp \u0111\u1eady c\u00f3 gio\u0103ng<\/td>\n<\/tr>\n
H\u1ed9p 4 Gang v\u00e0 H\u1ed9p \u0110a Gang L\u1edbn H\u01a1n<\/strong><\/td>\nChi\u1ec1u r\u1ed9ng b\u1ed9i s\u1ed1 c\u1ee7a ~2\u2033 m\u1ed7i gang, \u0111\u1ed9 s\u00e2u \u0111\u1ebfn 3\u20111\/2\u2033<\/td>\n40\u201380+ in\u00b3.<\/td>\nNhi\u1ec1u c\u00f4ng t\u1eafc t\u1ea1i m\u1ed9t v\u1ecb tr\u00ed<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

H\u1ed9p \u0111i\u1ec7n \u0111\u01a1n gang l\u00e0 lo\u1ea1i h\u1ed9p \u0111i\u1ec7n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ph\u1ed5 bi\u1ebfn nh\u1ea5t trong m\u00f4i tr\u01b0\u1eddng d\u00e2n c\u01b0; ch\u00fang th\u01b0\u1eddng c\u00f3 k\u00edch th\u01b0\u1edbc cao 3\u2033 v\u00e0 r\u1ed9ng 2\u2033. \u0110\u1ed9 s\u00e2u c\u1ee7a c\u00e1c h\u1ed9p kh\u00e1c nhau, v\u1edbi c\u00e1c ng\u00f4i nh\u00e0 c\u0169 c\u00f3 h\u1ed9p s\u00e2u 2-1\/4\u2033. Vi\u1ec7c l\u1eafp \u0111\u1eb7t c\u00e1c \u1ed5 c\u1eafm USB hi\u1ec7n \u0111\u1ea1i ho\u1eb7c \u1ed5 c\u1eafm th\u00f4ng minh c\u00f3 \u0111\u1ed9 s\u00e2u l\u1edbn h\u01a1n nhi\u1ec1u so v\u1edbi \u1ed5 c\u1eafm \u0111\u00f4i truy\u1ec1n th\u1ed1ng c\u00f3 th\u1ec3 g\u00e2y kh\u00f3 kh\u0103n v\u00ec thi\u1ebft b\u1ecb c\u00e0ng s\u00e2u th\u00ec vi\u1ec7c l\u1eafp \u0111\u1eb7t v\u00e0o h\u1ed9p qu\u00e1 n\u00f4ng c\u00e0ng kh\u00f3 kh\u0103n. M\u1ed9t h\u1ed9p qu\u00e1 n\u00f4ng s\u1ebd bu\u1ed9c b\u1ea1n ph\u1ea3i nh\u1ed3i nh\u00e9t d\u00e2y \u0111i\u1ec7n, \u0111i\u1ec1u n\u00e0y t\u1ea1o \u00e1p l\u1ef1c l\u00ean c\u00e1c k\u1ebft n\u1ed1i v\u00e0 c\u00f3 th\u1ec3 g\u00e2y ra hi\u1ec7n t\u01b0\u1ee3ng h\u1ed3 quang ho\u1eb7c m\u1ea1ch h\u1edf theo th\u1eddi gian. Do \u0111\u00f3, h\u1ea7u h\u1ebft c\u00e1c th\u1ee3 \u0111i\u1ec7n hi\u1ec7n nay \u0111ang s\u1eed d\u1ee5ng h\u1ed9p \u0111i\u1ec7n \u0111\u01a1n gang s\u00e2u 3-1\/2\u2033 nh\u01b0 ti\u00eau chu\u1ea9n, m\u1eb7c d\u00f9 quy chu\u1ea9n x\u00e2y d\u1ef1ng cho ph\u00e9p l\u1eafp \u0111\u1eb7t h\u1ed9p n\u00f4ng h\u01a1n. Th\u1ec3 t\u00edch th\u1ec3 t\u00edch th\u00eam trong h\u1ed9p ch\u1ec9 t\u1ed1n r\u1ea5t \u00edt chi ph\u00ed v\u00e0 l\u00e0m cho vi\u1ec7c l\u1eafp \u0111\u1eb7t ho\u1eb7c thay th\u1ebf thi\u1ebft b\u1ecb trong h\u1ed9p tr\u1edf n\u00ean d\u1ec5 d\u00e0ng h\u01a1n nhi\u1ec1u so v\u1edbi vi\u1ec7c s\u1eed d\u1ee5ng h\u1ed9p c\u00f3 \u0111\u1ed9 s\u00e2u n\u00f4ng h\u01a1n.<\/p>\n

\"C\u00e1ch<\/p>\n

C\u00e1ch Quy T\u1eafc 6\/12 \u1ea2nh H\u01b0\u1edfng \u0110\u1ebfn V\u1ecb Tr\u00ed v\u00e0 K\u00edch Th\u01b0\u1edbc H\u1ed9p<\/h2>\n

\u201cQuy t\u1eafc 6\/12\u201d l\u00e0 quy t\u1eafc kho\u1ea3ng c\u00e1ch, kh\u00f4ng ph\u1ea3i quy t\u1eafc k\u00edch th\u01b0\u1edbc h\u1ed9p, \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn s\u1ed1 l\u01b0\u1ee3ng v\u00e0 v\u1ecb tr\u00ed c\u00e1c h\u1ed9p b\u1ea1n c\u1ea7n cho vi\u1ec7c l\u1eafp \u0111\u1eb7t \u0111i\u1ec7n c\u1ee7a m\u00ecnh. Theo NEC \u0110i\u1ec1u 210.52, kh\u00f4ng \u0111i\u1ec3m n\u00e0o d\u1ecdc theo b\u1ea5t k\u1ef3 b\u1ee9c t\u01b0\u1eddng n\u00e0o \u0111\u01b0\u1ee3c c\u00e1ch xa \u1ed5 c\u1eafm \u0111i\u1ec7n h\u01a1n s\u00e1u feet. Do \u0111\u00f3, kh\u00f4ng \u0111\u01b0\u1ee3c v\u01b0\u1ee3t qu\u00e1 m\u01b0\u1eddi hai feet gi\u1eefa m\u1ed7i \u1ed5 c\u1eafm \u0111i\u1ec7n d\u1ecdc theo b\u1ea5t k\u1ef3 b\u1ee9c t\u01b0\u1eddng n\u00e0o. B\u1ea5t k\u1ef3 \u0111o\u1ea1n t\u01b0\u1eddng n\u00e0o d\u00e0i h\u01a1n hai feet ph\u1ea3i c\u00f3 \u00edt nh\u1ea5t m\u1ed9t \u1ed5 c\u1eafm \u0111i\u1ec7n \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t tr\u00ean \u0111\u00f3. \u0110i\u1ec1u n\u00e0y c\u00f3 ngh\u0129a l\u00e0 quy t\u1eafc 6\/12 thi\u1ebft l\u1eadp s\u1ed1 l\u01b0\u1ee3ng t\u1ed1i thi\u1ec3u tuy\u1ec7t \u0111\u1ed1i c\u1ee7a c\u00e1c h\u1ed9p \u1ed5 c\u1eafm trong m\u1ed9t ph\u00f2ng l\u1edbn v\u00e0 sau \u0111\u00f3 x\u00e1c \u0111\u1ecbnh s\u1ed1 m\u1ea1ch \u0111i\u1ec7n s\u1ebd \u0111\u01b0\u1ee3c cung c\u1ea5p c\u0169ng nh\u01b0 t\u1ed5ng t\u1ea3i t\u00ednh to\u00e1n cho b\u1ea3ng \u0111i\u1ec7n c\u1ee7a ph\u00f2ng \u0111\u00f3. Quy t\u1eafc 6\/12 l\u00e0 m\u1ed9t v\u00ed d\u1ee5 v\u1ec1 y\u00eau c\u1ea7u t\u1ed1i thi\u1ec3u; vi\u1ec7c l\u1eafp \u0111\u1eb7t th\u00eam \u1ed5 c\u1eafm, ngay c\u1ea3 khi v\u01b0\u1ee3t qu\u00e1 s\u1ed1 l\u01b0\u1ee3ng y\u00eau c\u1ea7u b\u1edfi quy t\u1eafc n\u00e0y, l\u00e0 \u0111\u01b0\u1ee3c ph\u00e9p v\u00e0 th\u01b0\u1eddng mang l\u1ea1i s\u1ef1 ti\u1ec7n l\u1ee3i b\u1ed5 sung. Hi\u1ec3u bi\u1ebft v\u1ec1 quy t\u1eafc 6\/12 s\u1ebd cho ph\u00e9p b\u1ea1n t\u1ea1o k\u1ebf ho\u1ea1ch \u0111i\u1ec7n ch\u00ednh x\u00e1c cho m\u1ed9t ph\u00f2ng \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed v\u00e0 k\u00edch th\u01b0\u1edbc ph\u00f9 h\u1ee3p c\u1ee7a t\u1eebng h\u1ed9p \u1ed5 c\u1eafm trong ph\u00f2ng d\u1ef1a tr\u00ean c\u00e1c d\u00e2y d\u1eabn ti\u1ebfp x\u00fac v\u1edbi ch\u00fang.<\/p>\n

Nh\u1eefng V\u1ea5n \u0110\u1ec1 C\u00f3 Th\u1ec3 X\u1ea3y Ra Khi H\u1ed9p Qu\u00e1 Nh\u1ecf<\/h2>\n

H\u1ed9p nh\u1ecf h\u01a1n k\u00edch th\u01b0\u1edbc quy \u0111\u1ecbnh c\u00f3 nh\u1eefng h\u1eadu qu\u1ea3 th\u1ef1c t\u1ebf. Khi m\u1ed9t h\u1ed9p b\u1ecb qu\u00e1 t\u1ea3i, k\u1ebft qu\u1ea3 s\u1ebd lu\u00f4n l\u00e0 l\u1edbp c\u00e1ch \u0111i\u1ec7n c\u1ee7a d\u00e2y d\u1eabn b\u1ecb suy gi\u1ea3m do nhi\u1ec7t b\u1ecb gi\u1eef l\u1ea1i; \u0111i\u1ec1u n\u00e0y s\u1ebd x\u1ea3y ra theo th\u1eddi gian. L\u1edbp c\u00e1ch \u0111i\u1ec7n tr\u1edf n\u00ean gi\u00f2n, v\u00e0 cu\u1ed1i c\u00f9ng, l\u1edbp c\u00e1ch \u0111i\u1ec7n s\u1ebd n\u1ee9t. M\u1ed9t d\u00e2y d\u1eabn b\u1ecb n\u1ee9t s\u1ebd t\u1ea1o ra l\u1ed7i n\u1ed1i \u0111\u1ea5t ho\u1eb7c ng\u1eafn m\u1ea1ch c\u00f3 th\u1ec3 kh\u00f4ng l\u00e0m nh\u1ea3y c\u1ea7u dao cho \u0111\u1ebfn khi h\u1ed3 quang \u0111\u00e3 b\u1eaft \u0111\u1ea7u. Ngo\u00e0i ra, n\u1ebfu h\u1ed9p qu\u00e1 n\u00f4ng, c\u00e1c d\u00e2y d\u1eabn s\u1ebd kh\u00f4ng th\u1ec3 \u0111\u01b0\u1ee3c g\u1ea5p g\u1ecdn g\u00e0ng ph\u00eda sau thi\u1ebft b\u1ecb; khi l\u1eafp \u0111\u1eb7t, c\u00e1c d\u00e2y s\u1ebd b\u1ecb n\u00e9n qu\u00e1 m\u1ee9c v\u00e0o ph\u00eda sau h\u1ed9p v\u00e0 c\u00f3 th\u1ec3 l\u00e0m l\u1ecfng v\u00edt \u0111\u1ea7u cu\u1ed1i ho\u1eb7c l\u00e0m g\u00e3y n\u00fat d\u00e2y do \u00e1p l\u1ef1c. C\u00e1c k\u1ebft n\u1ed1i kh\u00f4ng \u0111\u00e1ng tin c\u1eady t\u1ea1o ra v\u1ea5n \u0111\u1ec1 trong vi\u1ec7c ch\u1ea9n \u0111o\u00e1n s\u1ef1 c\u1ed1 \u0111i\u1ec7n v\u00e0 c\u00f3 th\u1ec3 g\u00e2y nguy c\u01a1 ch\u00e1y n\u1ed5. Tu\u00e2n theo ph\u00e9p t\u00ednh \u0111i\u1ec1n \u0111\u1ea7y h\u1ed9p s\u1ebd gi\u1ea3m b\u1edbt t\u1ea5t c\u1ea3 c\u00e1c v\u1ea5n \u0111\u1ec1 n\u00e0y.<\/p>\n

\"L\u1ef1a<\/p>\n

L\u1ef1a ch\u1ecdn h\u1ed9p ph\u00f9 h\u1ee3p cho c\u00f4ng vi\u1ec7c<\/h2>\n

Vi\u1ec7c ch\u1ecdn k\u00edch th\u01b0\u1edbc v\u00e0 ki\u1ec3u d\u00e1ng ph\u00f9 h\u1ee3p cho h\u1ed9p \u0111i\u1ec7n c\u1ee7a b\u1ea1n ph\u1ee5 thu\u1ed9c v\u00e0o lo\u1ea1i m\u1ea1ch \u0111i\u1ec7n b\u1ea1n \u0111ang l\u00e0m vi\u1ec7c, c\u0169ng nh\u01b0 s\u1ed1 l\u01b0\u1ee3ng d\u00e2y d\u1eabn s\u1ebd \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t c\u00f9ng trong m\u1ea1ch n\u00e0y. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 khuy\u1ebfn ngh\u1ecb th\u1ef1c t\u1ebf:<\/p>\n