There are an endless number of Bible studies you could do with co workers in the marketplace.
Below are listed just a few ideas to help you get started.
Study Genesis chapters 1-3 and the book of John which contains 21 chapters. If you discuss 2 chapters a week this is a 12 week study.
There is so much practical wisdom in the book of Proverbs for the marketplace as well as our lives in general. If you study and discuss 2 chapters a week this is a 15 to 16 week study.
In this study you can discuss some of the common words throughout the Bible and dig into their meaning. Words such as Redeemed, Grace, Mercy, Salvation, Sin, Righteousness, Faith, Disciple and so many more.
Invite curious co workers and tell them it will be an opportunity to ask questions and hear about why you believe what you believe. Discuss how God has changed your life. Have some apologetics available to discuss why it takes more faith to believe there is no God, than the truth that he is the creator of the universe and the Author of our Bible. Let them know how much He loves them.