Platforms sheltered or inside other structures (INDOORS) will not require wind or slow loads. This answer may be apparent from specifications or drawings, but not so apparent from a telephone request for quote.
Platforms outdoors and ABOVE GROUND (on buildings, etc.) will have larger gust factors for wind conditions.
Platforms in OPEN AND FLAT TERRAIN support HIGHER wind loads and LOWER snow loads. Platforms can be designed for worst case, but may be conservative and unnecessarijly uneconomical.
Building codes may vary by locality. The IBC (International Building Code) is becoming the standard; however, other applicable building codes may be BOCA, SBC, ANSI (now ASCE-7) or a local (city or state) code.
WIND LOAD is usually given in MPH.
SEISMIC DESIGN CATEGORY is to be designated. If unknown, design will default to ASCE-7.
SNOW LOAD is given in PSF (pounds per square foot). Local conditions may govern in mountain regions, the West Coast through the Rocky Mountains and the East Coast north of Massachusetts.
LIVE LOAD is usually given in PSF (pounds per square foot). Typical design platforms are:
- ACCESS PLATFORM (1-3 people, limited use) — 50 PSF.
- OPERATION PLATFORM (1-3 people, constant use) — 75 PSF.
- WORK PLATFORM (men with tools, portable equipment) — 100 PSF.
DEFLECTION CRITERIA is typically:
- Specified as 1/4" for the grating with 100 PSF LIVE LOAD (NOT necessarily the PLATFORM DESIGN LIVE LOAD)
- Specified as L/180 to L/360 for structural members (span in inches divided by 180 to 360, respectively)
CONCENTRATED LOADS are ADDITIONAL TO LIVE LOAD and may be permanent equipment, barrells or drums of chemicals, pallets for materials, boxes, etc. Obtain these LOADS in LBS., and possibly an area over which they act (i.e., pallets 4'x4' weighing 4,000 lbs. ea.).
HARDWARE REQUIRED
