Health & safety pointers:

Health and safety is a consideration not just for you, but for others in the deployment of pyrotechnics, this would include other players and members of staff.
Simple steps to be taken for all in airsoft and paintball activities would protect you from potential injuries or creating them.
1. Wear gloves
2. Wear full face protection
3. Wear safety glasses as a minimal safety measure ensure their specification is to en166.
4. Wear protective clothing
5. Take your time when deploying your v.t.g.
6. Good communications when deployment is conducted by shouting “grenade” or “frag out” warns players on both teams of a live v.t.g. is in effect.
7. Ear protection is a must and most reputable sites would have these freely available for all players and staff as a measure of good health and safety practice.

Other factors to consider upon deployment is that all blank firing devices produce a plasma flash, which is a result of burning black powder at high velocities could create a severe burn, so again safe deployment is a must do.
Deploy your v.t.g. at a wall or into a corner, but not near players, this type of deployment carries with some site operators as a distraction device, were other sites use the flash and bang as a kill device, this effects the game to suit site rules depending on the site operators rules and instructions.
If you are a site owner, it might be prudent to see if your insurance company offers cover for any pyrotechnics, v.t.g.’s and similar. Some devices are covered by some underwriters but not all. The same effects pyrotechnics also weather fuse or strike cap styles, again check with your policy holder.