1. When the thickness of the shotcrete cannot meet the design requirements, it should be sprayed separately, but the double-spraying time interval should not exceed 2 hours. Otherwise, the sprayed surface should be flushed with high-pressure water.
2. If excessive excavation or cracking occurs in the low pit area, operators should refill the sprayer and spray it.
3. It is forbidden to aim the sprayer at the person.
4. During the spraying process, if there is a malfunction such as blockage or power failure, immediately close the sluice and place the nozzle down.
5. During the work, if the pointer of the sprayer's pressure gauge is found to be abnormally swinging, that is, suddenly rising or falling, the operator should immediately stop and check the sprayer.
6. Operators should wear dust masks, latex gloves and glasses when spraying.
7. After the spraying work is completed, spray the water once every 7 days. After 7 days, spray once a day for 28 days.
8. Regularly check the strength of the concrete and repair the unqualified parts.
