This paper examines the key parameters for risk assessment near to oil/gas pipelines with particular reference to flames. In particular it examines outflow characteristics of the different fluids handled. It then examines the consequence modelling; more particularly the surface emissive powers of the flames, the failure rate data, the consequences using the Piper Alpha fireball and finally failure statistics. It is shown that the outflow characteristics are more complex than might be expected; the assessment of surface emissive powers has to be done with care; and finally, older pipelines distort the failure rate statistics or failure modes which are not relevant to a modem pipeline system. One specific conclusion of this paper is that the land-use planning zones round modem landlines may be reduced by more rigorous analysis of both effects of the leakage and the appropriate pipeline failure data, both in frequency and spectrum. This paper uses hitherto unpublished information and therefore some of the sources must remain confidential.