"You will be aware of hostile damaging comments on unofficial websites," he wrote in the letter which is also reproduced in the May issue of Journalist, the NUJ's member magazine.
"It would be extremely helpful if you could encourage chairmen either through public statements or match programmes to emphasis that our members are also victims of this situation and only seek to promote the best interests of football as they carry out their jobs during this difficult time."
Carlton and Granada's refusal to meet their contractual obligations has lead to a number of fans venting their anger in the wrong places, with a number of website set devoted to anti-ITV demonstations.
"We have very real concerns about the safety of our members inside and outside football grounds," the NUJ said in a recent statement.
"We hope that it's understood by all in football that our members are - like the fans themselves - people caught in the middle."