HVAC forms an essential part of the essential safety services onboard a rig and a part of the area classification requirements associated with electrical equipment. Your HVAC systems should prevent any potentially explosive or toxic gas-air mixtures entering non-hazardous areas such as living quarters.
The Battery Powered Temporary Refuge Unit fully complies with the requirements of HSE (Health and Safety Executive) and ISO. It was designed by Heinen & Hopman Engineering, a leading specialist in maritime air conditioning, central heating and cooling, and mechanical ventilation.
What are the requirements?
- HVAC systems should provide for a pressure differential in non-hazardous areas with all access doors closed of which is at least 50 Pa above that of the adjacent hazardous areas
- TR areas should have a pressure of between 50 and 75 Pa. in order to measure pressure decay over time. This is used to calculate an air leakage rate and a performance measure of the structure’s integrity (usually taken as 0.35 air changes per hour)
- Ensure speedy response to inlet-gas detection and time to stop the HVAC
- Take into account consequences for personnel and/or the atmosphere of a build-up of contaminants
- Maintain pressure in the TR area during an incident while ensuring sufficient air flow so that any leakage or other ingress (e.g. through the use of doors) is diluted and displaced
- Ensure availability of power sources to drive the HVAC system during an incident
The Heinen & Hopman solution
In response to a gas alarm, all HVAC exhaust systems will be switched off and the fire and gastight dampers closed. This will totally seal off the accommodation.
Our specially developed Temporary Refuge unit is not only sufficient for maintaining pressurisation in the TR area and keeping the accommodation at the ≥ 50 Pa. overpressure mark. It also serves as a battery powered HVAC unit.
Call in the experts
Prior to designing your customised HVAC system, a team from Heinen & Hopman Engineering will thoroughly investigate the onboard situation. This includes a pressure test using a certified blower door. If necessary a smoke generator will be used to find any leaks.
After testing, we will provide a comprehensive report with results and recommendations.
We recommend installing a TR unit with a capacity of at least 0.80 ac/hr, as doors will be opened several times during mustering. This capacity also ensures that an overpressure of 50 Pa will be reached within the shortest time possible.
The specially designed frequency drive fan is controlled by a pressure transmitter located in the accommodation.
Installation and design
The unit can be installed above the accommodation or the fresh air intake will be located near the top (minor concentration of potentially harmful gases). It will be self-supporting via battery power and explosion proof.
The unit is built from a frame made of double-walled Inox 316L steel plate (internally insulated) panels and provided with inspection doors. Delivered on frame, it includes:
- Inlet grill and motorised control damper (Ex)
- Pre filter, class G4, ATEX, Second filter, class F7, ATEX
- Purafil SP Blend, dual hydrocarbon filter, ATEX
- Fan, anti-sparkling,Ex-e/d + brass lining
- Fan motor, 1 x 230V / 50 Hz, Ex-II-2G-d-IICT4
- Motorised gastight damper, Ex, closing/opening time ≤ 4 sec
- H2S and CH4 sensors (Ex)
All projects are executed according to HSE management requirements.
Global maritime climate technology
Within the maritime sector Heinen & Hopman Engineering is globally renowned as an innovative and client-oriented business. In close cooperation with our clients, we realise smart solutions for the design, engineering and installation of tailor-made maritime climate systems. The Battery Powered Temporary Refuge Unit benefits from our decades of experience.