Friday Prayers - , Employees whose work means that they have to continue working at the time of Jumu’ah.

require the constant presence of an employee, including at the times
of obligatory prayers and Jumu'ah (Friday) prayers. Should these
employees leave their work and go and pray, or should they stay on the
job?
Praise be to Allaah.
The basic principle is that Jumu'ah prayer is obligatory upon
individuals, because Allaah says (interpretation of the meaning):
"O you who believe (Muslims)! When the call is proclaimed for the
Salaah (prayer) on Friday (Jumu'ah prayer), come to the remembrance of
Allaah [Jumu'ah religious talk (Khutbah) and Salaah (prayer)] and
leave off business (and every other thing). That is better for you if
you did but know!"
[al-Jumu'ah 62:9]
And Imam Ahmad narrated from Ibn Mas'ood (may Allaah be pleased with
him) that the Prophet (peace and blessings of Allaah be upon him) said
concerning some peoplewho were failing to attend Jumu'ah prayers: "I
had thought to tell a man to lead the people in prayer, then I would
burn down the houses of men who fail to attend Jumu'ah
prayers."(Ahmad, 1/402; Muslim, 1/452). Muslim narrated from Abu
Hurayrah and Ibn 'Umar (may Allaah bepleased with them) that they
heard the Messenger of Allaah (peace and blessings of Allaah be upon
him) say from the minbar: "There are people who should stop neglecting
Jumu'ah,or else Allaah will put a seal on their hearts, thenthey will
surely be among the negligent." And there is consensus among the
scholars on this point (that Jumu'ah is obligatory). But if a person
for whom Jumu'ah is obligatory has a legitimate shar'i excuse – such
as one who is directly responsible for a matter of national security
and protecting the interests of the ummah, and he is required to do
that job at the time of Jumu'ah, such as those who are incharge of
security, traffic, wireless and telephone communications, etc, those
whose shift happens to be at the time of the second call toJumu'ah
prayers or the time of a prayer in congregation – then such people are
excused for not praying Jumu'ah or prayers in congregation, because of
the general meaning of the verse (interpretation of the meaning):
"So keep your duty to Allaah and fear Him as much as you can"
[al-Taghaabun 64:16]
And the Messenger of Allaah (peace and blessings of Allaah be upon
him) said: "Whatever I forbid you to do, avoid it, and whatever I
command you to do, do as much ofit as you can." Moreover,such a person
has no lessan excuse than one who is excused because he fears for his
life or his wealth etc., who the scholars have said is excused for not
praying Jumu'ah or prayers in congregation so long as the reason is
present. But the obligation to pray Zuhr still stands, and he must
pray it on time; whenever he can pray in congregation he is obliged to
do that, as is the case with all the five daily obligatory prayers.
Fataawa al-Lajnah al-Daa'imah li'l-Buhooth