Should he shave his beard for the sake of work ?

Praise be to Allah.

Firstly: 

The command to let the beard grow is narrated in many saheeh ahadith which were narrated from the Prophet (peace and blessings of Allah be upon him), which indicates that it is obligatory to let the beard grow and it is haram to shave it. See question no. 1189. 

Secondly: 

It is part of the tolerant nature of Islam that it permits one to do something that is haram and to omit obligatory duties if there is a valid excuse for doing so, as in cases of necessity and urgent need – such as eating dead meat when forced to do so, or a woman being treating a male doctor when necessary. The matter is subject to shar’i guidelines and should not go any further than is necessary. 

Thirdly: 

The Muslim must strive to meet his needs without committing haram actions as much as possible. If he cannot do that except by committing a haram action, it is permissible for him to do it in that case. 

Based on the above, you should strive to do the following: 

1 – Look for a gas mask that can be worn with a beard. Some companies have made gas masks for religiously-committed Jews with beards who work for airline companies. 

2 – Look for another job which does not require you to commit any haram actions, even if that job is in another country. 

3 – Try to create your own work by doing business and the like. 

If you cannot do any of these things, then there is no sin on you, in sha Allah, if you shave your beard, so long as you shorten it only as much as is necessary; if you can manage to simply shorten it, then it not permissible for you to shave it off, and so on. Undoubtedly if a person fears Allah and keeps his duty to Him as much as he can, Allah will suffice him and grant him a way out, as Allah says (interpretation of the meaning): 

“And whosoever fears Allah and keeps his duty to Him, He will make a way for him to get out (from every difficulty).

3. And He will provide him from (sources) he never could imagine” [al-Talaaq 65:2-3]