Indoor safety device, a liquefied fuel gas system and a vehicle

1. An indoor safety device for a liquefied fuel gas system, wherein the liquefied fuel gas system comprises: at least one storage device storing liquefied fuel gas; a vent member arranged in fluid communication with the gas inside the storage device; and at least one safety valve arranged to automatically release gas from the storage device independent of the vent member when the pressure inside the storage device exceeds a predetermined first pressure value, the indoor safety device comprising:

a vent coupling;

a pressure relief valve configured to be arranged downstream of the vent coupling; and

a conduit for conveying gas comprising an inlet configured to be connected to the pressure relief valve,

wherein the indoor safety device is configured to be removably connected to the liquefied fuel gas system by connecting the vent coupling to the vent member,

wherein the pressure relief valve is configured such that it opens when the pressure inside the storage device exceeds a predetermined second pressure value to thereby vent gas from inside the storage device via the vent member and through the conduit, and

wherein the predetermined second pressure value is lower than the predetermined first pressure value, such that the pressure relief valve is configured to relieve pressure from the storage device prior to the pressure in the storage device reaching the first pressure value where gas would be released via the at least one safety valve to thereby prevent unwanted release of gas from the at least one safety valve.

2. The indoor safety device according to claim 1 , wherein the conduit is configured to convey the released gas to an outside environment.

3. The indoor safety device according to claim 1 , wherein the conduit for conveying gas is a flexible hose.

4. The indoor safety device according to claim 1 , wherein the predetermined second value is between 14-15.5 bar.

5. The indoor safety device according to claim 1 , wherein the vent coupling comprises a female quick disconnect valve, configured to be connected to the vent member of the liquefied fuel gas system.

6. The indoor safety device according to claim 1 , further comprising:

a restrictor configured to be arranged downstream of the vent coupling.

7. The indoor safety device according to claim 1 , wherein the pressure relief valve is configured to allow manual opening of the valve.

8. A liquefied fuel gas system, comprising:

at least one storage device storing liquefied fuel gas;

a vent member arranged in fluid communication with the gas inside the storage device;

at least one safety valve arranged to automatically release gas from the storage device independent of the vent member when the pressure inside the storage device exceeds a predetermined first pressure value; and

an indoor safety device comprising:

a vent coupling;

a pressure relief valve configured to be arranged downstream of the vent coupling; and

a conduit for conveying gas comprising an inlet configured to be connected to the pressure relief valve,

wherein the indoor safety device is configured to be removably connected to the liquefied fuel gas system by connecting the vent coupling to the vent member,

wherein the pressure relief valve is configured such that it opens when the pressure inside the storage device exceeds a predetermined second pressure value to thereby vent gas from inside the storage device via the vent member and through the conduit, and

wherein the predetermined second pressure value is lower than the predetermined first pressure value, such that the pressure relief valve is configured to relieve pressure from the storage device prior to the pressure in the storage device reaching the first pressure value where gas would be released via the at least one safety valve to thereby prevent unwanted release of gas from the at least one safety valve.

9. The liquefied fuel gas system according to claim 8 , wherein the vent member comprises a male quick disconnect valve, which requires connection to the vent coupling to open.

10. The liquefied fuel gas system according to claim 8 , wherein the indoor safety device is connected to the storage device when the system is in an indoor environment.

11. The liquefied fuel gas system according to claim 8 , further comprising:

a vent valve arranged upstream of the vent member,

wherein the vent valve is configured to be in an open position when the indoor safety device is used.

12. A vehicle comprising a liquefied fuel gas system comprising:

at least one storage device storing liquefied fuel gas;

a vent member arranged in fluid communication with the gas inside the storage device;

at least one safety valve arranged to automatically release gas from the storage device independent of the vent member when the pressure inside the storage device exceeds a predetermined first pressure value; and

an indoor safety device comprising:

a vent coupling;

a pressure relief valve configured to be arranged downstream of the vent coupling; and

a conduit for conveying gas comprising an inlet configured to be connected to the pressure relief valve,

wherein the indoor safety device is configured to be removably connected to the liquefied fuel gas system by connecting the vent coupling to the vent member,

wherein the pressure relief valve is configured such that it opens when the pressure inside the storage device exceeds a predetermined second pressure value to thereby vent gas from inside the storage device via the vent member and through the conduit, and

wherein the predetermined second pressure value is lower than the predetermined first pressure value, such that the pressure relief valve is configured to relieve pressure from the storage device prior to the pressure in the storage device reaching the first pressure value where gas would be released via the at least one safety valve to thereby prevent unwanted release of gas from the at least one safety valve.