Premises ceilings

The TLVs for airborne contaminants are based on the premise that although all chemical substances are toxic at some concentration for some period of time, a concentration exists for all substances from which no toxicity may be expected no matter how often the exposure is repeated. A similar premise holds for substances producing irritation, discomfort and nuisance. In using these limits, items such as excursion factors, ceiling values, "skin" notations, mixtures of substances, and inert material should be considered. These factors are discussed below. 

Typically, industrial premises have, in one space, zones with different activities, which require different target levels for the indoor environment and its control. These target levels may be determined for the whole area or locally. Also, often only a part of the space needs to be controlled. In addition to the main controlled zone, there may be one or more local controlled zones with targets different from those in the main controlled zone. For example, machines equipped with electrical components require a very clean and accurately controlled indoor environment, while the unoccupied zone near the ceiling needs only roughly controlled protection against structural damages. 

Automatic sprinkler systems have the great advantage that they are comparatively simple in concept and operate automatically, whether or not there are people present on the premises. Water is supplied from the public mains or tanks and pumps into a network of distribution pipes at ceiling level, which covers the whole premises. Water is discharged through nozzles or heads sited at regular intervals in the pipework, which are normally sealed with a he at-sensitive device. 

Community pharmacies should be easily accessible to the public and maintained in a clean condition. Walls, floors, ceilings and windows must be kept clean and surfaces should be impervious and easily wiped. The premises should have a clear area set aside for the preparation and compounding of medicinal products and diagnostic testing, and all pharmaceutical or non-pharmaceutical waste and expired or deteriorated items should be segregated in a separate area. When the pharmacy is closed, the shop window may be totally closed off with aluminium shutters for security purposes. 

From the above, it can be seen that Pressac s hypothesis as to the use of these areas for criminal purposes is based on fallacious premises from the very outset. It is also inexplicable on purely technical grounds. Despite the availability of two real hydrogen cyanide gas chambers which could have been converted for homicidal purpose by merely piercing holes in the ceiling for the introduction of Zyklon B, SS men are supposed to have put in an installation for homicidal gassings using carbon monoxide, and very early on, at that - but what for If homicidal gassings with Zyklon B worked perfectly at Auschwitz, as we are told they did, then why use carbon monoxide at Majdanek ... 

Those physical aspects of the premises that could affect the quality and safety of products. Buildings should be so designed and constructed as to prevent the entry of animals and insects interior surface (walls, floors and ceilings) should be smooth and free from cracks and open joints, should not shed particulate matter, and should permit easy cleaning and if necessary disinfection. 

The surfaces of the production premises, i.e. the walls, floors and ceilings, shall be as smooth as possible and free from cracks. Consequently, they shall propagate few particles and shall be easy to clean, and if necessary, to disinfect. 

What should be attended to in the assessment of the DS In premises intended for sterile and aseptic preparations (clean rooms) the most severe requirements apply to the walls, doors, floors, ceilings, heating and furniture, see further subsections. Premises which are only intended for non-sterile preparations can do with less far-reaching demands. Nevertheless in practice it might be wise to apply the requirements for sterile premises also for non-sterile premises if both are at stake. In the first place in a new building the itemisation of methods and materials between premises meant for sterile preparation and for non-sterile preparation usually doesn t yield much cost reduction. Additionally many of the starting points for the requirements for sterile preparations more or less apply to non-sterile . 

Refrigerators and freezers within the preparation premise are unwanted for several reasons such as that the expansion radiator at their backside cannot be cleaned. If a refrigerator or freezer in the preparation premise is indispensable it should be airtight separated from the room, e.g. by means of a flat shaft of sheets up to the ceiling or a throughput through the wall. 

Light fittings do easily attract dust as a consequence of their static electricity. Therefore they should be incorporated in the ceiling and be shut off by means of a glazed or transparent synthetic sheet. In classified premises no substantial air leakage must occur past the fitting. 

The reactor installation has its own steel leak-tight protective shell. The reactor compartment is closed by a protective guard consisting of multi-layered ceilings of the superstmcture roof, walls of the stern and bow machine rooms and the superstmcture premises. Altogether, these stmctures constitute the external protection of a reactor compartment capable of withstanding external physical impacts including an aircraft crash. 

The second also involves general ventilation of the room (Figure 6.14), without filtration of the exhaust. This is achieved by means of ceiling or wall mounted fans and a high volume of air is extracted (for example, a welding workshop must have between 3 and 15 air changes per hour in order for this method to be effective). It has a relatively low investment cost, but people on the premises still inhale any toxic fumes and again there is an enormous heat loss. 

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