Rev 3.09 6-1

INTOXILYZER 5000EN THEORY/OPERATION

Rev 3.09 6-2

Infra- Red Light Absorption

Infra - Red light is a form of energy known as:

ELECTROMAGNETIC RADIATION

The Electromagnetic Scale

Fast Slow

cosmic rays

gamma rays

x-rays

lightUltra-violet

visible infrared micro

wave

radiowave

Rev 3.09 6-3

All things will absorb

ELECTROMAGNETIC RADIATION

in their own

unique and consistent manner

Rev 3.09 6-4

THEREFOREAll things will absorb

INFRARED LIGHTin their own

unique and consistent manner

And will create their ownunique and consistent

absorption pattern

Rev 3.09 6-5

THE IR FINGERPRINTOF ETHANOL

3.47 Micron

Rev 3.09 6-6

SPECTROPHOTOMETRY

The science of measuring the absorption of light or radiant energy to identify and quantify a substance

Rev 3.09 6-7

BASIC SPECTROPHOTOMETRY PRINCIPLES

Less Concentrated/ Appears Lighter More Concentrated/ Appears Darker

Incidental Radiation

Emerging Radiation

Incidental Radiation

Emerging Radiation

Rev 3.09 6-8

SPECTROPHOTOMETER

An instrument that is able to use light or radiant energy to identify and quantify a substance

Rev 3.09 6-9

SPECTROPHOTOMETER(INTOXILYZER 5000EN)

An instrument that is able to use light (Infrared Light) or radiant energy to identify and quantify a substance (Ethanol).

Rev 3.09 6-10

SPETROPHOTOMETRIC RELATIONSHIPS

1. Measurements determine concentration.

2. Measurements are made relative to a standard (known) concentration.

3. Quantitative analysis is governed by

the BEER- LAMBERT LAW.

Rev 3.09 6-11

BEER - LAMBERT LAW

Absorption is directly

proportional to concentration.

Rev 3.09 6-12

BEER - LAMBERT LAW(GRAPHIC REPRESENTATION)

CONCENTRATION

A

B

S

O

R

B

A

N

C

E

Rev 3.09 6-13

INTERACTION OF INFRARED ENERGY WITH THE ETHANOL

MOLECULE

H

H H

H

H C C H C C

OH OH

H H H H

Rev 3.09 6-14

LightSource

Sample Chamber

LENS

LENS

Filter

the light striking the photo detector produces a level of energy labeled as X

BREATH SAMPLE ANALYSIS

STEP # 1

Photo Detector

Rev 3.09 6-15

LightSource

Sample Chamber

LENS

LENS

Filter

Photo Detector

Breath Sample In

Sample Out

The light striking the detector after alcohol isintroduced produces a different level of energylabeled as Y

The light striking the photo detector produces a level of energy labeled as X

STEP # 2

BREATH SAMPLE ANALYSIS

Rev 3.09 6-16

Infra-Red TheoryIf we establish the amount of IR light able to pass

through a chamber with no alcohol present

XThen establish the amount of IR light able to pass

through a chamber with alcohol present

YThen

X Y- = Alcohol Concentration

Rev 3.09 6-17

LightSource

Sample Chamber

LENS

LENS

Filter

Photo Detector

BREATH SAMPLE ANALYSIS

3.80 - Reference

3.36, 3.40, 3.52 - Interferents3.47 - Alcohol

Rev 3.09 6-18

ABSORPTION BAND OPTICAL FILTERS

(TRANSMITTANCE IN PERCENT)

REFERENCE 3.80 MICRONSETHANOL 3.47 MICRONS

TOLUENE 3.36 MICRONS

ACETONE 3.40 MICRONS ACETALDEHYDE, ISOPROPANAL, METHANOL, ETHER, ETC 3.52 MICRONS

WAVELENGTH IN MICRONS

Rev 3.09 6-19