While at work, if you have no choice, you can definitely either skip or, even better, postpone your sunnah prayers. If you did, you may make up the highly recommended sunnah prayers such as those before fajr, the ones before dhuhr and after, the one after isha, etc. There are precedents for this in the sunnah of the Prophet (peace be upon him). Once he was seen praying after 'asr and on enquiring about it, he said, "I was making up for the sunnah of dhuhr I skipped because of my preoccupations with the delegation of Bani Abd al-Qays."   Aishah also said, "If the Prophet (peace be upon him) missed the four rakahs of sunnah before dhuhr, he would pray them after 'asr."

Furthermore, Tirmidhi reports on the authority of Abu Hurayrah that the Prophet (peace be upon him) said, "If someone couldn't pray the two rak'ahs before fajr, let him pray them after the sun has risen."  Another report from Abu Sa'id al-Khudri states, "If anyone misses witr he should pray it whenever he wakes up or when remembers."

Based on such traditions, according to the majority of scholars, it is good to make up the sunnah prayers you miss later.