lighting
TRANSCRIPT
ALL INDIA INSTITUTE OF LOCAL SELF
GOVERNMENT
DELHI
“ Lighting Concepts for Paramedical”
DR.P.P.SINGH
By
Dr. P.P.SINGH
Faculty AIILSGD
Ex Medical Superintendent Cum Consultant pathologist HRH Delhi
Ex. Director India Population Project 8 Delhi..
SOURCE BOOKS OF AIILSG.
LIGHTING
WE WILL DISCUSS
– WHERE LIGHT COME FROM?.
-- NATURE OF LIGHT.
-- HOW LIGHT BEHAVE?.
-- HOW LIGHT IS MEASURED ?
-- HOW MUCH LIGHT IS
RECOMMENDED FOR VARIOUS
PURPOSES?
LIGHT SOURCES ARE;-
1. NATURAL FROM – SUN & STARS.
( CAN NOT BE CONTROLLED )
2. ARTIFICIAL - SOURCE THAT PEOPLE
CAN CONTROL.
IMPORTANCE OF SUN LIGHT.
--REQUIRED FOR HEALTHY GROWTH .
-- IS ALSO A DISINFECTANT.
-- VISIBLE LIGHT HAS SEVEN COLORS
(VIBGOYR )
-- INVISIBLE - INFRA RED & ULTRAVIOLET
-- GIVES FEELING OF HEALTH & VIGOUR.
-- GOOD SOURCE OF VITAMIN D + SKIN.
-- HELPS IN DEPOSITION OF CALCIUM IN
BONE.
ARTIFICIAL LIGHT
IT HELPS PEOPLE TO DO MANY THINGS THEY
COULD NOT DO WITHOUT NATURAL LIGHT. EX. ;-
-- TO RUN FACTORIES 24 HOURS A DAY.
-- FOR AUTOMOBILES , TRAINS AND AERO
-PLANE TO TRAVEL IN NIGHT.
ARTIFICIAL LIGHT COMES FROM ;-
-- ELECTRIC LAMPS.
--FLORESCENT LAMPS.
-- IN 1950 LASER WAS DEVELOPED.
( LASER IS THE DEVICE A NARROW BEAM OF
PHOTONS ALL OF WHICH HAVE SAME ENERGY.
THE LASER PRODUCE VERY PURE LIGHT OF
SINGLE COLOR.)
* LASER LIGHT HAS MANY USES IN
COMMUNICATION , INDUSTRY , MEDICINE AND
SCIENTIFIC LABORATORIES.
*PROPER AND ADEQUATE LIGHTING IS
ALWAYS REQUIRED FOR EFFICIENT VISION TO
REDUCE STRAIN ON EYE. AND TO REDUCE VISUAL
FATIGUE.
* LIGHT TRAVELS AT 2,99,792 KILOMETERS
( 1,86.282 MILES) PER SECOND.
CHARACTERISTIC OF PROPER LIGHT:
1. IT SHOULD BE SUFFICIENT FOR THE INTENDED USE.
2. IT SHOULD BE UNIFORM WITH SAME INTENSITY.
3. THERE SHOULD BE ABSENCE OF GLARE. ( ALWAYS AVOID IT
CAUSES ACUTE EYE DISCOMFORT.)
4. IT SHOULD BE STEADY. THERE SHOULD NOT BE FLICKERING
BUT CONSISTENCY.
5.THERE SHOULD BE ABSENCE OF SHARP SHADOW .
6. IT SHOULD BE NEARER TO THE DAY LIGHT.
NATURAL LIGHT COMES FROM VISIBLE
SKY AND PARTIALLY BY REFLECTION . THIS
CAN BE IMPROVED BY DIRECTION OF LIGHT .
REMOVAL OF ABSTENTIONS.
PROPER WINDOWS AND INTERIOR OF
ROOM PAINTED IN SUCH A WAY AS TO GIVE
COMFORTABLE CONTRAST . I.E. CEILING
SHOULD BE WHITE , THE UPPER PORTION OF
WALL BE LIGHT TINTED AND LOWER PORTION
SHOULD BE PAINTED SOME WHAT DARKER.
MEASUREMENT OF LIGHT
IT IS MEASURED IN UNIT CALLED FOOT CANDLE IN
BRITISH SYSTEM AND LUX IN METRIC SYSTEM.
IF SOURCE HAS A LUMINOUS INTENSITY OF 1
CANDLE THE MARKED AREA WILL GET LUMINOUS FLUX (
RATE OF LIGHT FALL ON IT )= 1 LUMEN
AN ILLUMINATION OF 1 FOOT CANDLE PRODUCED BY
1 LUMEN OF LIGHT SHINING ON AN AREA OF 1 SQ. FOOT.
AN ILLUMINATION OF 1 LUX IS PRODUCED BY 1
LUMEN OF LIGHT SHINING ON AN AREA OF 1 SQ. METRE.
INTENSITY OF LIGHT
IS INVERSELY WITH THE SQUIRE OF DISTANCE BETWEEN
SOURCE AND THE SURFACE.
= 1/ DISTANCE 2
THIS RELATION SHIP IS CALLED INVERSE SQUARE
LAW
IF THE DISTANCE OF 1 METRE IS MOVED TO 2 METRE
THEN SURFACE WILL RECEIVE (1/2)2 OR ¼ LUX OF LIGHT .
* STUDY OF LIGHT IS CALLED OPTICS .
* SCIENTIST HAS DESIGNED –
MICROSCOPES, TELESCOPES AND OTHER
OPTICAL INSTRUMENTS .
BIOLOGICAL EFFECTS OF LIGHT;-
IT INFLUENCES BODY TEMPERATURE .
IT INFLUENCES PHYSICAL ACTIVITIES .
IT HELPS THE ACTIVATION OF VIT. D.
IT HELPS TO METABOLIZE & EXCRETE
THE BILLIRUBIN.
WAYS OF ARTIFICIAL LIGHTING:
1. DIRECTLY : 99 – 100% ON
WORKING AREA.
2.SEMI DIRECT : 10 – 40% UPWARDS.
3.IN DIRECT : 90 – 100% LIGHT
PROJECTED TO CEILINGS.
4. SEMI INDIRECT : 60 – 90% UPWARDS.
5. DIRECT – INDIRECT : 50% UPWARDS
AND 50% ON OBJECT.
RECOMMENDED ILLUMINATION
1. CASUAL READING 100 LUX.
2. GENERAL OFFICE WORK 400 LUX.
3. FINE ASSEMBLY 900 LUX.
4. WATCH MAKING 2000- 3000 LUX.
NORTH LIGHT
* STRONG SUNLIGHT CAUSES A GLARE
IS HARMFUL TO SIGHT.
*THE SUN LIGHT FROM NORTH SIDE IS
MORE EFFECTIVE AND STEADY .
*THUS LIGHT TO THE INDUSTRIES ARE
USUALLY PROVIDED THROUGH WINDOWS &
VENTILATORS ON TOP OF THE WALL ON THE
NORTH SIDE THEREFORE CALLED “ NORTH
LIGHT’
LIGHTING OF CLASS ROOMS OF SCHOOL:
1. THE MINIMUM HEIGHT OF CLASS ROOM SHOULD BE 3.5
MTS (12 FEET)
2.THE MINIMUM AREA OF CLASS ROOM SHOULD BE 40
SQUARE METRE ( 6.3MT X 6.3 MTS ) 400 SQ.FT.( 20 X20
FEET)
3. THE CLASS ROOM SHOULD DERIVE THEIR MAIN LIGHT
FROM NORTH. WINDOWS SHOULD BE PLACED AT REGULAR
DISTANCE SO TO ENSURE UNIFORM OF LIGHT.
4. THE TOTAL WINDOW AREA SHOULD BE1/5TH OF FLOOR
AREA AND AT LEAST ½ OF THESE SHOULD ON THE NORTH .
5.SKY LIGHT SHOULD NEVER BE PROVIDED.
6. IF THERE IS DEFICIENCY OF LIGHT , NORTH LIGHT
SHOULD BE PROVIDED.
7. WHEN THE SCHOOL BUILDING IS ON A NARROW STREET
AND TALL BUILDING S ARE EXISTING ON THE OPPOSITE
SIDE , THE LIGHT OF SCHOOL CAN BE IMPROVED BY
FREQUENTLY WHITEWASHING THE WALLS TO REFLECT
LIGHT.