National Standards as applies on the 433A

The National Standard is a fixed set of  expense. It is a figure set by the IRS and the Department of Labor. If you go to our website to the home page, click the toolbar marked IRS forms, see the  National Standards, you will find the applicable chart. Call us if you have problems finding the landing page.
You will find the Standard that fits your situation.
National Standards: Food, Clothing and Other Items include the following expenses:
Apparel and services. Includes shoes and clothing, laundry and dry cleaning, and shoe repair.
Food. Includes all meals, home and away.
Housekeeping supplies. Includes laundry and cleaning supplies; other household products such as cleaning and toilet tissue, paper towels and napkins; lawn and garden supplies; postage and stationary; and other miscellaneous household supplies.
Personal care products and services. Includes hair care products, haircuts and beautician services, oral hygiene products and articles, shaving needs, cosmetics, perfume, bath preparations, deodorants, feminine hygiene products, electric personal care appliances, personal care services, and repair of personal care appliances.
Miscellaneous.
IRS allows taxpayers the total national standard amount for their family size without questioning the amount actually spent. Other rules apply but you will need a tax professional for help in this area.
Local Standards set forth by the IRS and the Department of Labor

Local standards include the following expenses:
Housing and Utilities. Housing expenses include: mortgage (including interest) or rent, property taxes, necessary maintenance and repair, homeowner’s or renter’s insurance, homeowner dues and condominium fees. The utilities include gas, electricity, water, heating oil, bottled gas, trash and garbage collection, wood and other fuels, septic cleaning, telephone and cell phone. Usually, these expenses are considered necessary only for the primary place of residence. Any other housing expenses should be allowed only if, based on a taxpayer’s individual facts and circumstances, disallowance will cause the taxpayer economic hardship.
Generally the total number of persons allowed for determining family size should be the same as those allowed as exemptions on the taxpayer’s most recent year tax return. There may be reasonable exceptions, such as foster children or children for whom adoption is pending.
An allowance for cell phone expenses has been included in the Housing and Utility standards. If a taxpayer claims a separate cell phone expense on the financial statement, the amount would be added to the housing and utility expense claimed and subject to the allowable amount for the Housing and Utility standards. Ensure the taxpayer is not duplicating this expense.
Taxpayers are allowed the standard amount for housing and utilities or the amount actually spent, whichever is less. If the amount claimed is more than the total allowed by housing and utilities standards, the taxpayer must provide documentation to substantiate those expenses are necessary.
When deciding if a deviation is appropriate, consider the cost of moving to a new residence; the increased cost of transportation to work and school that will result from moving to lower-cost housing and the tax consequences. The tax consequence is the difference between the benefit the taxpayer currently derives from the interest and property tax deductions on Schedule A to the benefit the taxpayer would derive without the same or adjusted expense.
All deviations from the housing and utilities standards must be verified, reasonable and documented in the case history.
Transportation.
This includes vehicle insurance, vehicle payment (lease or purchase), maintenance, fuel, state and local registration, required inspection, parking fees, tolls, driver’s license and public transportation. Public transportation includes mass transit fares for a train, bus, taxi, etc., both within and between cities.
Transportation expenses are considered necessary when they are used by taxpayers and their families to provide for their health and welfare and/or the production of income. Employees are expected to exercise appropriate judgment in determining whether claimed transportation expenses meet these standards. Expenses that appear to be excessive should be questioned and, in appropriate situations, disallowed
When determining the allowable amounts, allow the full ownership standard amount, or the amount actually claimed and verified by the taxpayer, whichever is less. Allow the full operating standard amount, or the amount actually claimed by the taxpayer, whichever is less. Substantiation for the operating allowance is not required unless the amount claimed exceeds the standard.
There is a single nationwide allowance for public transportation. This allowance is established as a floor for individuals with no vehicle. Taxpayers with no vehicle are allowed the standard, per household, without questioning the amount actually spent. The taxpayer is not required to provide documentation unless the amount claimed exceeds the standard.
If a taxpayer owns a vehicle and uses public transportation, expenses may be allowed for both, provided they are needed for the health and welfare of the individual or family, or for the production of income. However, the expenses allowed would be actual expenses incurred. Documentation would not be required unless the amount claimed exceeded the standards.
Consider availability of public transportation if car payments (purchase or lease) will prevent the tax liability from being paid in part or full. Public transportation could be an option if it does not significantly increase commuting time and its use is not unrealistic. You should also consider the age, health and needs of minor children when requesting the taxpayer use public transportation in lieu of vehicle expenses
If a taxpayer has a car, but no car payment, only the operating costs portion of the transportation standard is used to figure the allowable transportation expense.
A single taxpayer is normally allowed ownership and operating costs for one vehicle. The taxpayer is allowed the standard for ownership and operating costs, or the amounts actually spent, whichever is less.
Please see the below link for the National Standards
http://www.irs.gov/individuals/article/0,,id=96543,00.html