Clean Start: Back to Work Tax Credit Act This bill allows employers a business related tax credit for 50% of the cost of qualified cleaning expenses incurred in a trade or business or with respect to owning or operating commercial real estate. The credit may not exceed $250,000 for any taxpayer in a taxable year and it terminates after March 31, 2022. The bill defines qualified cleaning expenses as amounts paid for cleaning services, cleaning products, tools, machinery, technology systems, personal protective equipment, and for obtaining a certification in cleaning.