(CNN) -- Rants about your boss or your job may have once been reserved for during after-work drinks at a bar, but employee gripes are now being voiced in the social media sphere.
The National Labor Relations Board issued a complaint against a Connecticut ambulance service company after it fired a worker for posting unflattering and sometimes vulgar comments about her boss on Facebook.
The organization accused the company of illegally terminating Dawnmarie Souza and denying her access to union representation during an investigatory review. The federal agency is arguing that Souza's criticism of her boss on Facebook is generally "a protected concerted activity."
But workers should still be wary about what they post on social media sites. About a quarter of employers surveyed by the Society of Corporate Compliance and Ethics in 2009 had disciplined an employee for improper activities on social networking sites. If a worker posts something negative, and a manager finds it, he or she can legally be fired, some employment attorneys say.
CNN asked experts on social media etiquette in the workplace: How can you engage in online forums without losing your job?
1. Think before you post
Imagine if the comment you posted or tweeted will appear in the local newspaper the next day, says Tyson B. Snow, an employment attorney at Manning Curtis Bradshaw & Bednar LLC in Utah. While that rule of thumb may sound extreme, Snow says it is a safe way to manage your content.
On a social media site, the audience is unlimited, and the content is permanent. An employee may post one photo and quickly remove it, but someone could still archive the page or make a copy, he says.
2. Be picky about who you friend
Only allow people you trust into your social network, says Shanti Atkins, president of ELT Inc., an ethics and compliance training company. Instead of casually accepting all the co-workers or managers who ask to friend you, be selective about who you allow to view your posts.
Atkins says employees may forget who they let into their network and that could lead to problems later on.
3. Do it on your own time and computer
Try to limit your Facebook and Twitter activity to your personal computer, several experts say. If you engage in problematic activity on the company property and time, this can provide the managers more leverage, say several workplace experts.
Many employers and workplaces already ban the sites at the workplace to prevent social media spats from becoming an issue.
4. Watch what you post at home
Many workers are unaware that mentioning their company in a negative light on the internet -- even if it's done on personal time at home -- could lead to disciplinary measures, says John Lusher, a social media consultant. He says many organizations have departments that monitor social media comments and photographs that pertain to the company.
5. Keep the dialogue positive
Social media can be a great way to foster conversations about an employee's recent promotion or a company event, says Josh Whitford, president of Echelon Media, a company that specializes in social media. But, he says, certain topics such as trade secrets should never be disclosed online.
6. Figure out privacy settings
Social media privacy settings may be tricky, but take the time to consider all the different settings, says Shanti Atkins, at ELT Inc. She suggests implementing filters and grouping co-workers and bosses so that certain information does not reach everyone.
7. Learn your employee rights
Employees need to make the effort to understand corporate policy regarding the use social media at work and at home, says Tyson Snow, an employment attorney. However, most companies don't have such policies in place. Only 10 percent of companies had specific polices to deal with social networking sites, according to The Society of Corporate Compliance and Ethics.