In the wake of Friday’s shooting at the Empire State Building of Jeffrey Johnson’s rage against his former boss, this causes us to pause and of course, grieve.

As we look at signs of a disgruntled co-worker, boss or direct report, it’s important to notice some red flags.

According to the Occupational Safety & Health Administration’s (OSHA) site, about two million American workers are victims of workplace violence each year and no one is immune.

Gary Kessler, associate professor of homeland security at Embry-Riddle Aeronautical University, told The Wall Street Journal, “You have to look for the signs and signals. Do they own weapons? Do they talk a lot about shooting as a solution to problem? Do they seem angry? Do they make threatening statements?”

Others may not be so forthright with their words. Instead, try to detect their emotions. They may become irritable, have a history of mental illness, have frequent arguments with colleagues and/or bosses, and demonstrate a disheveled appearance, as pointed out in the piece.

The key take-away though is similar to the motto on public transit here in NYC: “If you see something, say something.”

If your colleague seems out of it and consistently gets worse, tell a boss, get help. If they’re no longer employed similar to the late Johnson, it’s still important to speak up even if someone perhaps in your community.

To file an official complaint by phone, report an emergency, or get OSHA advice, assistance, or products, call their office at (800) 321-OSHA (6742).