ABSTRAK
Gas Metering Station CNOOC SES Ltd di Cilegon adalah fasilitasuntuk serah terima gas dari pihak CNOOC SES Ltd kepada PLTGU Cilegondengan jumlah penyerahan gas sekitar 80 juta kaki kubik per hari yangberlokasi di Kecamatan Pulo Ampel Kabupaten Serang Propinsi Banten.Bahaya yang timbul dari kegiatan operasi Gas Metering Station ini adalahbahaya kebakaran akibat kebocoran gas dari fasilitas yang ada antara Iain :slug receiver, closed drain dmm, pig receiver, filter coalescer & metering skidserta pipa penyalur serta kemungkinan terjadinya Iedakan. Penelitian yangdilakukan merupakan penelitian analitis deskritif dengan melakukan analisadan perhitungan terhadap faktor-fakior yang menyebabkan terjadinya bahayakebakaran dan ledakan serta level keparahan (severity) yang mungkin terjadi.Metode yang dipergunakan adalah melakukan sectioning di Gas MeteringStation, penghitungan frekuensi kebocoran berdasarkan data yang ada didalam E&P Forum, menilai scenario kebakaran yang mungkin terjadi denganmetode ETA-Event Tree Analysis, menilai severity yang mungkin timbuldengan menggunakan acuan Health & Safey Executive Standard sertamenentukan hazardous area dengan menggunakan tabel dari Canada Gasinstitute. Gas Metering dapat dibagi menjadi 5 section yakni : slug receivenclosed drain drum, pig receiver; filter coalescer & metering skid dan pipapenyalur dengan scenario berdasarkan safety protection philosophy sebagaiberikut : Kemungkinan Percikan - Alarm Sukses - Emergency Shutdown -Blowdown System - Fire Protection Sukses - Trend Teijadinya Kebakaran.Frekuensi kebakaran per tahun untuk masing-masing section adalah sebagaiberikut : slug receiver (5.2x10?), closed drain drum (3.8 x10"), pig receiver (2.2x 10"), rilter coalescer & metering skid (5 x10"?) dan pipa penyalur (7.5x10??).Event outcome sebagai hasil Event Tree Analysis beserta nilainya adalahsebagai berikut : Gas Bocor -> Percikan Langsung -> BDS Sukses -> JetFire (0.00E+OO), Gas Bocor -> Percikan Langsung -> BDS Gagal -> Jet Fire(3.07E-02), Gas Bocor -> Percikan Langsung ~> FPS Sukses -> Eksplosion (0.00E+0O), Gas Bocor -> Percikan Langsung -> FPS Gagal -> Eksplosion(1 .62E-03), Gas Bocor -> Percikan Menyusul -> BDS Sukses -> Flash Fire(0.00E+00), Gas Bocor -> Percikan Menyusul -> BDS Gagal -> Flash Fire(1 .62E~03), Gas Bocor -> Deteksi Gagal -> ESD Sukses -> BDS Sukses ->FPS Sukses (8.08E-05), Gas Bocor -> Deteksi Gagal -> ESD Gagal -> BDSGagal (4.25E-06). Pada keadaan teriadi kebakaran maka severitymempunyai level significant dengan kecepatan gas terbakar 0.57 lgq/detikselama 125 detik, dan tangki bahan bakar solar PLTGU Cilegon dalamkeadaan aman. Dengan program perawatan peralatan fire protection systemdi Gas Metering Station dan pelatihan tanggap darurat untuk personil diIapangan, diharapkan severity level dapat ditekan menjadi minor bahkan tidakterjadi.

---

ABSTRACT
The risk of Gas Metering Station operation is the gas leakage of the followingequipment such as: slug receiver, closed drain drum, pig receiver, filtercoalescer & metering skid which potentially result a tire and followed by aexplosion. The research- design is analytical descriptive by performinganalysis and calculation of the related factors produces a tire and explosionand its level of severity. The sequences of research are as follow: GasMetering Station sectioning, calculate frequency refering the E&P Forumdatabase, assessment of the Ere scenario by using ETA-Event Tree Analysis,assessment of the Severity by using Health & Safety Executive Standard anddetermine the hazardous area by using Canada Gas Institute table. GasMetering Station consists of 5 sections i.e. slug receiver, closed drain drum,pig receiver, filter coalescer 8. metering skid and pipeline. Refer to the safetyprotection philosophy of Gas Metering Station, the sequences of a fire asfollow: Initial Ignition - Alarm Success - Emergency Shutdown success -Blowdown System Success - Fire Protection System Success and Escalationof fire occurrence. The fire frequencies per year for each seclioning are asfollow: slug receiver (5.2x10"), closed drain drum (3.8 x10??), pig receiver (2.2 x10??), filter coalescer & metering skid (5 x1 O"?) and pipeline (7.5x10?°).The eventoutcome of event tree analysis including the values are as follow:Gas Leaking ~> Immediate Ignition -> BDS Success -> Jet Fire (0.00E+00),Gas Leaking -> Immediate Ignition -> BDS Fail -> .let Fire (3.07E-02),Gas Leaking -> Immediate Ignition -> FPS Success -> Explosion (0.00E+O0),Gas Leaking -> Immediate Ignition -> FPS Fail -> Explosion (1.62E~03),Gas Leaking -> Lagging Ignition -> BDS Success -> Flash Fire (0.00E+0O),Gas Leaking -> Lagging ignition -> BDS Fail -> Flash Fire (1 .62E-03), Gas Leaking -> Detector Fail -> ESD Success -> BDS Success -> FPSSuccess (8.08E-05),Gas Leaking -> Detector Fail -> ESD Fail -> BDS Fail (4.25E-06)ln case of ire occurs, the severity will be signiticant level with gas leak flowrate is 0.57 kgs/second during 125 seconds and the PLTGU Cilegon fuelstorage tank is in safe condition.By implementing the tire protection system maintenance program and regularpersonnel training for emergency response, the severity level of Gas MeteringStation will be minor and expected to be zero.

---