Mandatory To Conduct 'Air Blank Test' To Ensure Breath Analyser Has 'Zero' Calibration Before Taking Sample : Kerala High Court

The Kerala High Court recently passed a judgment directing the Director General of Police (DGP) to issue necessary directions to the police officers of the State to mandate conduct of Air Blank Test and ensure that the calibration is at 'zero' before subjecting a person to the breathalyser test.

Justice V.G. Arun observed, "it is essential to note that the purpose of conducting an Air Blank Test is to check for any residual alcohol before taking breath sample from a person using a breath alcohol testing device. Thus, the primary goal of a blank test is to verify that the breathalyzer is functioning correctly and is not influenced by any residual alcohol from previous tests. Therefore, it is mandatory to conduct an Air Blank Test and ensure that the calibration is at 'zero' before taking breath sample using a breath alcohol testing device."

The Court was hearing a Criminal Miscellaneous Case (Crl.M.C.) by the petitioner seeking to quash the criminal proceedings after a crime was registered against him for allegedly driving his scooter in a rash and negligent manner under the influence of alcohol.

As per the prosecution case, the offences alleged against the petitioner were those under Section 281 [Rash driving or riding on a public way] of the Bharatiya Nyaya Sanhita (BNS) along with Sections 185 [Driving by a drunken person or by a person under the influence of drugs], 3(1) [Necessity for driving licence] and 181 [Driving vehicles in contravention of Section 3 or Section 4] of the Motor Vehicles Act (MV Act).

However, the petitioner denied all these offences and submitted that he was not subjected to medical tests or breathalyser test in accordance with law.

According to the petitioner, the breathalyser test ought to have been conducted immediately after the police stopped his vehicles but in reality, it was done much later. It was also contended that he was not subjected to medical test within two hours of his arrest as mandated under Section 204 of the MV Act.

The petitioner also contended that the reading of the breathalyser test was not at 'zero' calibration immediately before the petitioner's breath sample was taken to detect presence of alcohol. Therefore, the breathalyser test marking the alcohol content in his presence cannot be relied on.

He relied on a Circular issued by the Director General of Civil Aviation, which made it mandatory to run an Air Blank Test on the instrument and obtain the reading '0.000' before each breathalyzer test for personnel engaged in aircraft maintenance, air traffic control services, aerodrome operations and ground handling services.

Accepting the contentions of the petitioner, the Court held that offences under Section 185, 3(1) and 181 of the MV Act are not attracted since the petitioner was holding a valid licence and since there was no acceptable evidence regarding alcohol level in his blood.

However, the Court opined that evidence has to be adduced to determine whether the offence under Section 281 BNS would be attracted or not.

Therefore, the Court allowed the Crl.M.C. in part by by quashing the final report and further proceedings against the petitioner for the offences under Sections 185, 3(1) and 181 of the Motor Vehicles Act alone.

The Court also directed the Public Prosecutor to give a copy of the order to the Director General of Police.

Case Title: Saran Kumar S. v. State of Kerala and Anr.

Case No: Crl.MC No. 5442 of 2025

Citation: 2025 LiveLaw (Ker) 435

Counsel for the petitioner: Faheem Ahsan S.

Counsel for the respondents: M.C. Ashi, Sr. Public Prosecutor

Click To Read/Download the Judgment