Breath Analyzer & Alcohol Effects


DGCA - Aircraft rule 24 - Prohibition on consumption of intoxicating and psychoactive substance.

The use of alcohol and drugs by pilots is regulated by DGCA. Among other provisions, this regulation states that no person may operate or attempt to operate an aircraft:

  • within 8 hours of having consumed alcohol
  • while under the influence of alcohol
  • with a blood alcohol content of 0.04% or greater
  • while using any drug that adversely affects safety

Alcohol & Its Effects

  • Alcoholic beverages, used by many to "unwind" or relax, act as a social "ice-breaker," is a way to alter one's mood by decreasing inhibitions.
  • Alcohol consumption is widely accepted, often providing the cornerstone of social gatherings and celebrations.
  • Along with cigarettes, many adolescents associate the use of alcohol as a rite of passage into adulthood.
  • While its use is prevalent and acceptable in our society, it should not come as a surprise that problems arise in the use of alcohol and the performance of safety-related activities, such as driving an automobile or flying an aircraft.
  • These problems are made worse by the common belief that accidents happen "to other people, but not to me." There is a tendency to forget that flying an aircraft is a highly demanding cognitive and psychomotor task that takes place in an inhospitable environment where pilots are exposed to various sources of stress.

What Alcohol Does

  • It's a sedative, hypnotic, and addicting drug.
  • Alcohol quickly impairs judgment and leads to behavior that can easily contribute to, or cause accidents.

Facts About  alcohol

  • Alcohol is rapidly absorbed from the stomach and small intestine, and transported by the blood throughout the body. Its toxic effects vary considerably from person to person, and are influenced by variables such as gender, body weight, rate of consumption (time), and total amount consumed.
  • The average, healthy person eliminates pure alcohol at a fairly constant rate - about 1/3 to 1/2 oz. of pure alcohol per hour, which is equivalent to the amount of pure alcohol contained in any of the popular drinks . This rate of elimination of alcohol is relatively constant, regardless of the total amount of alcohol consumed. In other words, whether a person consumes a few or many drinks, the rate of alcohol elimination from the body is essentially the same. Therefore, the more alcohol an individual consumes, the longer it takes his/her body to get rid of it.
  • Even after complete elimination of all of the alcohol in the body, there are undesirable effects-hangover-that can last 48 to 72 hours following the last drink.
  • The majority of adverse effects produced by alcohol relate to the brain, the eyes, and the inner ear-three crucial organs to a pilot.
  • Brain effects include impaired reaction time, reasoning, judgment, and memory. Alcohol decreases the ability of the brain to make use of oxygen. This adverse effect can be magnified as a result of simultaneous exposure to altitude, characterized by a decreased partial pressure of oxygen.
  • Visual symptoms include eye muscle imbalance, which leads to double vision and difficulty focusing.
  • Inner ear effects include dizziness, and decreased hearing perception.
  • If other variables are added, such as sleep deprivation, fatigue, medication use, altitude hypoxia, or flying at night or in bad weather, the negative effects are significantly magnified.

What is a Breath Analyser

  • A breath analyzer,  is a battery-operated device that can reveal a person's blood alcohol content (BAC) by sampling the breath breath.

  •  Law enforcement has used breathalyzers for many years, but a breath analyzer can also be handy for individuals.

  • Party guests can avail themselves of a breathalyzer to ensure they can legally and safely get behind the wheel to drive home.

  • If the reading is still too high, a simple waiting period can help one avoid a disciplinary action.

  • Institutions and business with policies of random alcohol monitoring might use a breath analyzer, especially among employees that are entrusted with the care of others, work with potentially dangerous machinery or operate vehicles.

  • A breath analyzer can detect BAC because alcohol does not change chemical composition within the body. Instead, it is absorbed by the stomach and intestines to enter the bloodstream. Inside the bloodstream it travels throughout the body, including lung sacs called alveoli, where alcohol molecules are mixed with exhaled air.

  • The ratio for alcohol found in the breath to alcohol in the blood is 2,100:1. Hence, by measuring the concentration of alcohol in the, the Breath analyzer can easily calculate blood alcohol content. The legal limit in most states is 0.08% BAC.

Procedure for pre flight testing

How alcohol affects pilot performance

  • Pilots have shown impairment in their ability to fly an ILS approach or to fly IFR, and even to perform routine VFR flight tasks while under the influence of alcohol, regardless of individual flying experience.
  • The number of serious errors committed by pilots dramatically increases at or above concentrations of 0.04% blood alcohol. This is not to say that problems don't occur below this value. Some studies have shown decrements in pilot performance with blood alcohol concentrations as low as the 0.025%.

Hangovers are dangerous

  • A hangover effect, produced by alcoholic beverages after the acute intoxication has worn off, may be just as dangerous as the intoxication itself.

  • Symptoms commonly associated with a hangover are headache, dizziness, dry mouth, stuffy nose, fatigue, upset stomach, irritability, impaired judgment, and increased sensitivity to bright light.

  • A pilot with these symptoms would certainly not be fit to safely operate an aircraft. In addition, such a pilot could readily be perceived as being "under the influence of alcohol."


Keep in mind that regulations alone are no guarantee that problems won't occur. It is far more important for pilots to understand the negative effects of alcohol and its deadly impact on flight safety.

General Recommendations

  1. As a minimum, adhere to all the guidelines of DGCA
  2. 8 hours from "bottle to throttle"
  3. do not fly while under the influence of alcohol
  4. do not fly while using any drug that may adversely affect safety
  5. A more conservative approach is to wait 24 hours from the last use of alcohol before flying. This is especially true if intoxication occurred or if you plan to fly IFR. Cold showers, drinking black coffee, or breathing 100% oxygen cannot speed up the elimination of alcohol from the body.
  6. Consider the effects of a hangover. Eight hours from "bottle to throttle" does not mean you are in the best physical condition to fly, or that your blood alcohol concentration is below the legal limits.
  7. Recognize the hazards of combining alcohol consumption and flying.
  8. Use good judgment. Your life and the lives of your passengers are at risk if you drink and fly.

Alcohol avoidance is as critical as developing a flight plan, a good preflight inspection, obeying ATC procedures, and avoiding severe weather.


Total avoidance of alcohol should be a key element observed by every pilot in planning or accomplishing a flight.