Right outside of Qom, Iran, there are a number of brick makers. Most are using some modern type of technology but there are many who still make bricks using 5000 year old technology: mud.
The men in the video are Afghani migrant workers who work for an Iranian owned business. The sun is scorchingly hot but the air very dry. The head scarfs help to provide shelter from the sun and even more relief from the heat when they are dipped in water.