Please guide me how to draft a mail to all the employees mentioning about the professional behavior and be soft spoken with each other and senior departments?

Dear All,
I have noticed in my work place, any one comes and starts screaming for any thing. These type of behavior shall not be acceptable.
Kindly, guide how shall I communicate this to employees so that my purpose is served to stop this kind of attitude in future.

More than writing a mail or letter to all departments, one needs to examine as to why everyone is stressed out to keep shouting.
What for do they shout and what is the response to the shouting?
This matter can be discussed with your seniors and then in interdepartmental meeting with all HODs.
A line of action can then be chalked out with seniors themselves involving themselves in making a culture change.

Dear Richa,
This is in addition to what Nathraoji has said. Part of the first sentence of his reply says "one needs to examine as to why everyone is stressed out to keep shouting". Let me explain his sentence. People get frustrated because of the following reasons:
a) Unresponsive colleagues
b) Incomplete work
c) Delay in completion of work
d) Inaccuracies in work
e) Seniors' expectations are perceived as unreasonable by the Managers are unable to oppose them. However, they download their frustration on their juniors.
Now it appears that expressing frustration on others has become routine. It has become routine because your top leadership did not bother to foster a culture of healthy interpersonal environment.
The issue may be discussed with the top leadership and with his consent, this point may be brought for discussion in Managers' meeting. As Mr Nathrao has said, let the solution come from them.
Lastly, if the top leadership themselves do not exercise patience or lacks interpersonal skills, then nothing will change. Please remember the proverb fish begins to rot from head. If the head is rotten then don't expect body to remain healthy!
Thanks,
Dinesh Divekar

Dear Richa kumari,
I do not believe that the behaviour of screaming and shouting at your workplace, regardless of reasons, is so rampant that all the staff as a matter of habit indulge in it every now and then. If it so, then it is far more serous malady and point to something basically wrong with the organisation requiring surgical treatment. I hope it is not so.
It must a few who display such behavior at times on some provocation or even habitually . Any communication/actions to curb this behavior must be directed to such employees, as large number of them are well behaved most of the times.
Most crucial action in the process of bringing out desired behavioural change, is when those who are in leadership roles are seen 'walking the talk'. When leaders are seen talking in soft, respectable and dignified manner, it becomes contagious and others are very likely to follow them and thus a culture starts to take a footprint.
Yet there will be some who lack self-control and refuse to fall in line due to personal or situational provocation either occasionally or habitually.
Such people are to be dealt with progressive disciplinary actions, and must eventually be weeded out despite having given enough opportunities to improve.
In my view, above actions will prove to be far more powerful than mere circular or communication in meetings.
Regards,
Vinayak Nagarkar
HR- Consultant

Dear Ms. Richa Kumari:
"Shouting' in any professional environment, whatever the reason, is just not in.
When things go amiss, when procrastination becomes part of the work culture, when deadlines are nor met, targets are not achieved, or there is something fundamentally wrong with the communication culture, then instead of working out the reasons for all such set backs, an easy way out is to lose your cool , give a piece of your mind and begin a blame game. Shouting also distances peoples.
Like VN pointed out , there must be an attitudinal and cultural change - ever seen a charismatic leader - whatever the situation, whatever the need, he steers to answers through a smiling disposition and talks at a pitch , audible yet soft.
More and better work gets done in the absence of shouting.
NEVER, repeat never, shout !
Regards
Arif ur Rehman