The Cullen Report into the Piper Alpha disaster (Cullen, 1990) recommended that a temporary refuge (TR) should be provided on all offshore installations. The Temporary Refuge is required to have a defined performance standard related to its survivability when exposed to a major accident that includes, but is not limited to, ingress of smoke, flammable and toxic gas. HVAC forms an essential part of this.As the Temporary Refuge is the last space for the crew before abandoning the vessel, rig or platform, the HVAC system should create and maintain a comfortable and safe indoor condition free of any explosive and/or toxic gas-air mixtures.The air quality and pressure inside the Temporary Refuge zone is than of top priority. This can be created by our special Temporary Refuge pressurization unit (TR-unit).Our TR-unit basically consists of an explosion proof fan, a filter section that filtrates H2S & SO2 and optionally a heater. The power supply is coming from the vessels Uninterrupted Power Supply (UPS) system or optionally by a battery power pack to ensure operation at all times.

Our TR unit provides clean filtered fresh air, free from H2S & SO2 contaminates in an over pressured Temporary Refuge area. Three levels of filtration (G4, F7, and active carbon) is applied to incoming air before being supplied to the TR.The control system constantly compares inside and outside pressures and LEL’s, and should the TR area pressurization or LEL levels fail, provide a visual and/or audible warning.Our TR unit is designed for external installation to TR areas with a supply duct to the TR area interior. The TR unit control panel is designed to be installed internally within the TR area.When the TR unit is operational the unit is designed as a fail-safe system, i.e. should the unit sustain damage or an air seal leaks, then clean air will leak out of the unit rather than contaminated air being drawn in.During normal operation is the TR unit “dead” and closed by gastight dampers. It comes operational for emergency situations.Please don't hesitate to contact us for more information.

Our employees are eager to answer all your questions. Download the TR Unit PDF for more detailed information H&H Temporary Refuge Unit.pdf BSD-109: Pressures in Buildingshow to clean lg split ac indoor unit Abstract:  Air flow in buildings is one of the major factors that governs the interaction of the building structure with the mechanical system, climate and occupants. samsung air conditioner parts melbourneIf the air flow at any point within a building or building assembly can be determined or predicted, the temperature and moisture (hygrothermal or pyschometric) conditions can also be determined or predicted. car air conditioning repairs oxfordshireIf the hygrothermal conditions of the building or building assembly are known, the performance of materials can also be determined or predicted.

Rights: Building Science Digests are information articles intended for professionals. The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered. The author and publisher make no warranty of any kind, expressed or implied, with regard to the information contained in this article. The information presented in this article must be used with care by professionals who understand the implications of what they are doing. If professional advice or other expert assistance is required, the services of a competent professional shall be sought. The author and publisher shall not be liable in the event of incidental or consequential damages in connection with, or arising from, the use of the information contained within this Building Science Digest. Building Science Experts' Session CAT is one of the leading suppliers of Central HVAC equipments such as Air Cooled Chillers, Double-skin AHU's, FCU's, Chilled Water Pumps, Exhaust Fans, Pressurization Units, Cooling Tower etc. 

CAT represents world renowned manufacturers like TACO-USA for Chilled Water Pumps and Pressurization System Units; Blue Star-India for Central HVAC equipments; Markey SPX for Cooling Tower Equipments; SKM make DX airconditioning equipment and systems and Thermoscreens-UK for air curtains.Central Airconditioning & Trading services is founded on the following principles and complies with all international standards: Business Integrity- CAT is strongly committed to business integrity and strictly complies with laws and regulations that govern business activities in our market. Our technical team get involved with conusultants / developers into early stage of project design and offer most efficient, economical and reliable HVAC products and solutions. All enquiries are responded immediately including site visits / inspections. All our Application Engineers, Service Engineers and Technicians are factory trained by our principals for Equipment selection, Installation checks, Testing, Commissioning, Trouble-shooting, Servicing etc.

80/20 Pressurizing/Recirculating Direct-Fired Heating & Cooling System Arizon’s 80/20 Pressurizing/Re-Circulating Indirect or Direct-Fired Heating and Cooling System provides customers with the benefits of building pressurization control and air re-circulating capabilities all in one unit. Available in a fixed or modulating control operation, Arizon’s system can re-circulate between 0 and 80% of the inside conditioned air in a building while pressure-controlling the space and providing between 20% and 100% fresh, outside air. By combining building pressurization and air re-circulation in one system, we prevent both unconditioned outside air from migrating into the space while continuously re-circulating the inside conditioned air to provide higher efficiency versus competitors 100% make-up air alternatives. High efficiency 80/20 pressurization/re-circulation system Heating capacities up to 16,800,000 BTU’s Air volumes up to 130,000 CFM Cooling capacities up to 450 tons

Unit Information and Options • 30:1 burner turndown on direct-fired equipment • Up to 18:1 burner turndown on indirect-fired equipment • Horizontal roof or thru wall-mount, outdoor vertical-mount, indoor suspended, horizontal mezzanine • Hot water, steam, oil, gas, LP or electric heating sources. • Remote burner flame safeguard controls with flame • 304 or 409 stainless steel heat exchangers • Variety of discharge configurations • U.V. flame detection, automatic gas modulation, low fire start, low airflow switch • Cast aluminum burners with stainless steel mixing plates • DX, chilled water, ammonia, and evaporative cooling available • Fan bearings rated to a minimum of 100,000 hours (L-10 Life) • NEMA 5 remote control panel, NEMA 3R Main Electrical Panel • 1 year parts warranty and fully factory tested • Single or double wall construction • G90 galvanized or painted finish