Tecpilot,
JAR-OPS 3 in the latest version is more specific than you indicate in your post; in the ACJ which contains the conceptual text it makes this distinction:
7 HEMS operational sites
The HEMS philosophy attributes the appropriate levels of risk for each operational site; this is derived from practical considerations and in consideration of the probability of use. The risk is expected to be inversely proportional to the amount of use of the site. The types of site are:
HEMS operating base; from which all operations will start and finish. There is a high probability of a large number of take-offs and landings at this heliport and for that reason no alleviation from operating procedures or performance rules are contained in the HEMS appendix.
HEMS operating site; because this is the primary pick up site related to an incident or accident, its use can never be pre-planned and therefore attracts alleviations from operating procedures and performance rules - when appropriate.
The hospital site; is usually at ground level in hospital grounds or, if elevated, on a hospital building. It may have been established during a period when performance criteria was not a consideration. The amount of use of such sites depends on their location and their facilities; normally, it will be greater than that of the HEMS operating site but less than for a HEMS operating base. Such sites attract some alleviations under the HEMS rules.
The recommended size for a
HEMS Operating Site is given also in guidance (i.e. it is not a requirement):
IEM to Appendix 1 to JAR-OPS 3.005(d), sub-paragraph (c)(2)(i)(C)
HEMS operating site
See Appendix 1 to JAR-OPS 3.005(d) sub-paragraph (c)(2)(i)(C)
When selecting a HEMS operating site it should have a minimum dimension of at least 2D. For night operations, unsurveyed HEMS operating sites should have dimensions of at least 4D in length and 2D in width.
With regard to hospital sites; the Public Interest Site Appendix was written specifically with German hospitals in mind.
Jim