Move over OSHA. Construction employers and others in more than 20 states are facing changes in laws involving guns on workplace property. The various legal modifications address the liability of a business if a weapon is used on an employer’s property. “Some companies have taken the changes in stride, but others are rewriting their human-resources policies, training employees to detect early signs of employee aggression and considering extra security for tense situations like termination meetings,” writes Sara Murray, at The Wall Street Journal. How does this affect workers at construction sites and background checks?