To limit the probability that live building services [e.g. electrical installations] will be damaged during demolition operations, which could lead to a fire or explosion, which could lead to harm to persons.
To limit the probability of the unwanted release of flammable liquids or vapours from live building services [e.g. gas and fuel lines] during demolition operations, which could lead to their accumulation in ignitable concentrations, which could lead to a fire or explosion, which could lead to harm to persons.