Security roofs

Secure roof hatches from the inside and have alarm contacts on the hatch. 

A note of caution about roof fasteners. A common mistake is to fix a galvanised or aluminium roof in place with nails or screws of a different metal copper or brass, for instance. The copper acts as cathode, and the zinc or aluminium corrodes away rapidly near to the fastening. A similar sort of goof has been known to occur when copper roofing sheet has been secured with steel nails. As Fig. 24.6 shows, this sort of situation leads to catastrophically rapid corrosion not only because the iron is anodic, but because it is so easy for the electrons generated by the anodic corrosion to get away to the large copper cathode. 

The security system can be considered as layers of protection. Physical barriers and deterrents constitute not only the building stmcture itself, made up of walls, doors, windows, floor and a roof, but the yard around the building and probably a perimeter fence or wall. 

Roof openings, including roof lights and ventilation, should be treated, from a security point of view, in the same way as openings, located elsewhere in the building fabric. 

In many cases, it is necessary to complement physical security by the installation of an intruder alarm system in order to achieve the standard of security commensurate to the risk exposure. The scope of protection to be afforded by the alarm system depends on the security risk, but it may embrace fences, windows, doors, roofs, walls, internal areas, yards and external open areas, and vehicles inside and outside buildings. There is a comprehensive range of detection devices, but the choice of detector is critical to ensure that it provides the desired level of protection and is stable in the particular environment. 

The placement of fume hood exhaust motors is an important fire protection consideration. Fume hood exhaust motors should be placed on the roof of the building or in a fire secured penthouse. 

Walls or roofs tend to block vision and access, trap sand, debris, and reduce ventilation so that flammable vapors are not as quickly dispersed. They may also collapse if there is an explosion or deflagration. They can therefore contribute to secondary effects by falling onto pipes an equipment that may substantially exceed damage from the original explosion or deflagration. They can also lead to a false sense of security. 

Headed studs are normally used to secure a roof slab to a structural steel framing system for rebound loads in new designs. This option may not available for upgrading existing structures. It may be necessary to provide through bolts to the structural frame with a backing plate on the top side of the stab. 

My master had his priorities, but I had mine. I gobbled my dinner and made all speed for Violetta. The fastest route was by way of the roof, of course, but if the security at Number 96 was as tight as it should be, I might have to spend more time explaining myself than I would save. I ran downstairs instead. 

PV panels can be mounted in many different ways. They can be secured to racks that stand on poles, or be ground mounted, or put on roofs, for instance. 

In the tank, the sheet joints at the roof and at the floor level should be as shown in Figure 8.3c, i.e., at the floor. The sheet end from the shell should be laid below the floor sheets, and not vice versa and the sheet end at the roof should be laid beneath the shell sheet. A 1 mm security strip of 50 mm wide should be laid on the joints. 

Teams of roof inspectors followed the clearing gangs. As they encountered areas of bad roof they either inserted temporary wooden props, or where necessary brought down all the loose stone to reveal the more secure stratum above. At first men more familiar with colliery techniques worked as safety men, but following an early fatal accident only Bath stone quarrymen were so employed. The accident occurred on Saturday... 

They were living in a small apartment house inside the special security area. The entrance was commanded by a machine gun manned by two constables of the Palestine Police, ensconced behind a sandbag wall on the roof of the garage. Another constable guarded the door and carefully... 

Hurricane clip- Metal straps that are nailed and secure the roof rafters and trusses to the top horizontal wall plate. Sometimes called a Teco clip. 

According to the analysis of three parts on the transverse and three parts on the vertical and the 9 meters roof which consists of layered limestone. We use the support method in the mining face, it ensures the secure withdraw of the equipments in the fully mechanized mining face, combined with the conditions of the roof and floor. 

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