Breath/Blood Tests & Conroe DWI Charges

Decades Spent Serving Clients in Montgomery, TX

In Texas, the definition of "intoxicated" includes having a blood alcohol concentration (BAC) of 0.08 percent or more. In order to determine your BAC, the law enforcement officer will ask you to submit to either a blood test or breath test, which will be conducted at the local hospital (although it can sometimes be taken at the jail).

Although a "failed" or "refused" breath or blood test may impact your chances of avoiding a DWI conviction, Conroe DWI attorney Doug Atkinson can work to challenge this evidence against you, whether it is physical evidence or the arresting officer's testimony.

Schedule a free consultation with Douglas W. Atkinson, Attorney at Law today by calling (936) 681-0031 or contacting the firm online.

Understanding the Breath Test

A breath test is conducted on a machine called an Intoxilyzer which uses the spectroscopy method—measuring the amount of light that is absorbed in a particular substance. The higher the concentration, the more light is absorbed and the higher the readout.

How Is It Administered?

You will be asked to blow into a mouthpiece. The air goes through a heated tube. Once the air enters the main chamber, light is shined into the cylinder.

The breath sample will absorb the light at a certain rate. The more light that is absorbed, the higher the concentration of alcohol. The machine will then compute the light absorption into a BAC value.

Are the Results Accurate?

The government wants to use the results of the Intoxilyzer to prosecute you. However, there are many fallacies in the Intoxilyzer.

For instance, a few areas of malfunction may include:

• The machine is only periodically checked for proper function and accuracy
• The machine tests itself to determine if is malfunctioning
• The machine is not required to perform perfectly by law
• The machine has a rate of error of 0.02 allowable between the two breath specimens
• The machine may be contaminated by previous users
• The machine is not warrantied by the manufacturer to read accurately
• The machine assumes everyone tested will have the same blood/breath ratio
• The machine cannot tell what your BAC was at the time of driving
• A fever may cause the machine to read higher
• Some substances in your body may cause the machine to read incorrectly even though they are not alcohol
• Radio frequency interference can cause the Intoxilyzer to read incorrectly
• Mouth alcohol from belching can cause abnormally high readings
• GERD or acid reflux can cause the Intoxilyzer to read incorrectly