Metal Cases

DOE-STD-3020-2005

5.4.3.2

Metal Cases: Metal cases shall have a double-turned, 3/4 in. (19

mm) wide flange on each face or a gelatinous seal socket or sleeve

as specified in the procurement documents. Cases shall be

assembled by riveting or bolting the corners with fasteners that

comply with Section 5.4.3.3. Panels shall be assembled into the

case by potting a subassembly consisting of the filter pack and side

panels into the top and bottom panels (but not the corners), using an

adhesive meeting the requirements of Section 5.3.4. For

mechanically joined panels the space between abutting panels shall

be sealed with an adhesive meeting the requirements of Section

5.3.4. There shall be no rough edges that might penetrate or cut

workers' gloves or injure the fingers of personnel handling the filters.

5.4.3.3

Fasteners : Approved fasteners for the assembly of metal HEPA

filter cases are listed below:

Stainless steel bolts: 300 series per ASTM A 320 or ASTM

A 193

Stainless steel nuts: 300 series per ASTM A 194

Stainless steel lock washers: 300 series per ASME B18.21.1

Stainless steel plain washers: 300 series per ASME B18.22.1

Stainless steel rivets: 300 series per ASTM A 581

Approved fasteners for the assembly of wooden HEPA filter cases

are listed below:

Nails: carbon steel, galvanized, zinc coated, aluminum per

ASTM F 1667

Staples: carbon steel, galvanized, zinc coated, aluminum per

ASTM F 1667

5.4.4

Gaskets : Gaskets shall be glued firmly and continuously to the case. Loose,

peeling, or distorted gaskets shall be cause for rejection of the filter. The

gasket shall not extend more than 1/16 in. (1.6 mm) over either side of the

seating surface at any point. Gaskets may be of one-piece or made up of

strips joined at the corners by keyhole, keystone, or other interlocking type

joints. Edges of the joint area shall be thoroughly coated with adhesive

(sealant meeting requirement of Section 5.3.4) before assembly.

5.4.5

Face Guards : Face guard edges shall be firmly embedded in adhesive and

fabricated so that projecting wires or edges do not form a puncture hazard to

personnel handling the filter and do not project onto or beyond the gasket

mounting surface. Wire edges formed when slitting or shearing face guards

shall be smoothed on both surfaces of the material before installation.