What is the ruling on working in quality control for carbon dioxide gas used by soda and alcoholic beverage companies? Is there a sin incurred by doing so?

It is forbidden for the company to sell carbon dioxide to a company that uses it in the production of alcohol. If the questioner's brother is not directly involved in selling the gas to such companies, then there is no sin upon him, as long as the gas is not specifically designated for sale to the alcohol company, and his work is limited to monitoring the quality of gas manufacturing without handling its sales affairs.