The legalization of marijuana in the U.S. has been getting more attention in the past months, with Utah and Missouri as the latest states to approve medical use of cannabis in November. To date, there are 33 states allowing medically prescribed cannabis, with 10 states also approving recreational marijuana use. 

These changes are taking place due to the growing awareness of the advantages or health benefits of using marijuana in the country. With the public and the government’s acceptance, businesses are encouraged to rethink about the zero-tolerance attitude against marijuana use at the workplace. 

The legalization of marijuana demands employers to "closely examine current policies, or their absence, tied to marijuana usage, update or change them as they see fit, and relay as much detail as possible," Dan Rowland, a Denver-based marijuana-policy industry consultant, told Inc. Magazine

He pointed out that companies should promote proper awareness, particularly of the change in marijuana laws and its application to office policies. Employers should explain to workers how off-duty access to pot might affect work, Rowland added. 

Here are what employers can do to address workplace use of marijuana:

1. Remove marijuana from drug test concerns

In states where recreational use of marijuana is allowed, employers can remove marijuana from drug testing. Peter Cappelli, director of the Center for Human Resources at the Wharton School, said instead of finding out if one used pot in the past month as part of the hiring decision, employers should focus on identifying skills. 

"It seems a little weird to think we are so interested in whether somebody has used marijuana in the last month rather than whether they've got the skills to perform the job," he said. 

Cappelli also raised a good question about the legality and effects of marijuana compared to alcohol.

 "Are you testing for alcohol use, which is also legal but impairs behavior? And the answer is, virtually never," he said.  

2. It is still right to say no

Despite being legal in a state where the company is based, companies can still ban the use of marijuana on the job. It is the same way with how drinking alcohol is prohibited during office hours. 

A no-tolerance policy regarding marijuana would help avoid human resources issues, such as the link between performance and pot. In Colorado, state laws allow companies to add to their policies a ban on recreational marijuana on the job, which many business have already implemented. 

3. Support medical marijuana

It is already considered a legal drug. Some workers might have to take prescribed medical marijuana during office hours to treat major conditions. The drug has been known to help treat epileptic conditions, PTSD, Crohn's disease, nausea, cancer, multiple sclerosis and chronic pain.

For employees suffering from such conditions, not using marijuana might be the one that could affect their performance.