He will probably want to roll with comfort and some discreet style first - really much more likely to be mugged with a knife or gun than a sniper rifle...
I personally like this one a waistcoat on Amazon no one can tell its bulletproof very discreet:
http://www.amazon.com/gp/product/B00O07GQW0
NIJ IIIA Bulletproof Waistcoat
by Body Armor Pro
3.1 out of 5 stars 9 customer reviews
Available from these sellers.
Size: XX-Large
NIJ IIIA certification. This material will resist up to a .44 mag, or 9mm submachine gun.
Lightweight 4.5 - 5.9 lbs (dependent on size)
Vital organ coverage, front and back.
Removable waterproof cover, easy clean.
Available in 5 sizes. Fully adjustable.
.44 Mag or 9MM submachine guns multiple shots is a pretty good rating for vital organs front or back still skull is - would need a kevlar balaclava and helmet - not so discreet in the workplace etc
A lot of different bullet proof vests to compare note you get what you pay for...:
http://www.bodyarmoroutlet.com/body-armor.html
Good to know about vest ratings:
https://en.wikipedia.org/wiki/Personal_armor
While many standards exist, a few standards are widely used as models. The US National Institute of Justice ballistic and stab documents are examples of broadly-accepted standards. Since the time that NIJ started testing, the lives of more than 3,000 officers were saved.[16] In addition to the NIJ, the United Kingdom's Home Office Scientific Development Branch (HOSDB—formerly the Police Scientific Development Branch (PSDB)) standards are also used by a number of other countries and organizations. These "model" standards are usually adapted by other countries by following the same basic test methodologies, while changing the specific ammunition tested. NIJ Standard-0101.06 has specific performance standards for bullet resistant vests used by law enforcement. This rates vests on the following scale against penetration and also blunt trauma protection (deformation):[17]
In January 2012, the NIJ introduced BA 9000, body armor quality management system requirements as a quality standard not unlike ISO 9001 (and much of the standards were based on ISO 9001).
Armor Level (Higher is better)Protection
Type I
(.22 LR; .380 ACP)This armor would protect against:
2.6 g (40 gr) .22 Long Rifle Lead Round Nose (LR LRN) bullets at a velocity of 329 m/s (1080 ft/s ± 30 ft/s); and
6.2 g (95 gr) .380 ACP Full Metal Jacketed Round Nose (FMJ RN) bullets at a velocity of 322 m/s (1055 ft/s ± 30 ft/s).
It is no longer part of the standard.
Type IIA
(9 mm; .40 S&W; .45 ACP)New armor protects against:
8 g (124 gr) 9×19mm Parabellum Full Metal Jacketed Round Nose (FMJ RN) bullets at a velocity of 373 m/s ± 9.1 m/s (1225 ft/s ± 30 ft/s);
11.7 g (180 gr) .40 S&W Full Metal Jacketed (FMJ) bullets at a velocity of 352 m/s ± 9.1 m/s (1155 ft/s ± 30 ft/s); and
14.9 g (230 gr) .45 ACP Full Metal Jacketed (FMJ) bullets at a velocity of 275 m/s ± 9.1 m/s (900 ft/s ± 30 ft/s).
Conditioned armor protects against:
8 g (124 gr) 9 mm FMJ RN bullets at a velocity of 355 m/s ± 9.1 m/s (1165 ft/s ± 30 ft/s);
11.7 g (180 gr) .40 S&W FMJ bullets at a velocity of 325 m/s ± 9.1 m/s (1065 ft/s ± 30 ft/s); and
14.9 g (230 gr) .45 ACP Full Metal Jacketed (FMJ) bullets at a velocity of 259 m/s ± 9.1 m/s (850 ft/s ± 30 ft/s).
It also provides protection against the threats mentioned in [Type I].
Type II
(9 mm; .357 Magnum)New armor protects against:
8 g (124 gr) 9 mm FMJ RN bullets at a velocity of 398 m/s ± 9.1 m/s (1305 ft/s ± 30 ft/s); and
10.2 g (158 gr) .357 Magnum Jacketed Soft Point bullets at a velocity of 436 m/s ± 9.1 m/s (1430 ft/s ± 30 ft/s).
Conditioned armor protects against:
8 g (124 gr) 9 mm FMJ RN bullets at a velocity of 379 m/s ±9.1 m/s (1245 ft/s ± 30 ft/s); and
10.2 g (158 gr) .357 Magnum Jacketed Soft Point bullets at a velocity of 408 m/s ±9.1 m/s (1340 ft/s ± 30 ft/s).
It also provides protection against the threats mentioned in [Types I and IIA].
Type IIIA
(.357 SIG; .44 Magnum)New armor protects against:
8.1 g (125 gr) .357 SIG FMJ Flat Nose (FN) bullets at a velocity of 448 m/s ± 9.1 m/s (1470 ft/s ± 30 ft/s); and
15.6 g (240 gr) .44 Magnum Semi Jacketed Hollow Point (SJHP) bullets at a velocity of 436 m/s (1430 ft/s ± 30 ft/s).
Conditioned armor protects against:
8.1 g (125 gr) .357 SIG FMJ Flat Nose (FN) bullets at a velocity of 430 m/s ± 9.1 m/s (1410 ft/s ± 30 ft/s); and
15.6 g (240 gr) .44 Magnum Semi Jacketed Hollow Point (SJHP) bullets at a velocity of 408 m/s ± 9.1 m/s (1340 ft/s ± 30 ft/s).
It also provides protection against most handgun threats, as well as the threats mentioned in [Types I, IIA, and II].
Type III
(Rifles)Conditioned armor protects against:
9.6 g (148 gr) 7.62×51mm NATO M80 ball bullets at a velocity of 847 m/s ± 9.1 m/s (2780 ft/s ± 30 ft/s).
It also provides protection against the threats mentioned in [Types I, IIA, II, and IIIA].
Type IV
(Armor Piercing Rifle)Conditioned armor protects against:
10.8 g (166 gr) .30-06 Springfield M2 armor-piercing (AP) bullets at a velocity of 878 m/s ± 9.1 m/s (2880 ft/s ± 30 ft/s).
It also provides at least single hit protection against the threats mentioned in [Types I, IIA, II, IIIA, and III].
In addition to the NIJ and HOSDB standards, other important standards include: the German Police's Technische Richtlinie (TR) Ballistische Schutzwesten,[18] Draft ISO prEN ISO 14876,[19][20][21] and Underwriters Laboratories (UL Standard 752).[22]
Textile armor is tested for both penetration resistance by bullets and for the impact energy transmitted to the wearer. The "backface signature" or transmitted impact energy is measured by shooting armor mounted in front of a backing material, typically oil-based modelling clay. The clay is used at a controlled temperature and verified for impact flow before testing. After the armor is impacted with the test bullet the vest is removed from the clay and the depth of the indentation in the clay is measured.[17]
