No 11837, Friday 28 Oct 2016, Gridman

ACROSS
1   Peter's hollow attempt to squelch rifts in modification of factory's watchword (6,5) SAFETY FIRST {SAFE}{TrY} {RIFTS}* What's the role of modification if squelch is the AInd?
9   He leaves city-dweller for the French thief (7) BURGLAR BURG{-he+la}LAR
10 Ruler put on in a month (7) MONARCH {M{ON}ARCH}
11 Strap hothead in Chinese secret society (5) THONG {T{Hot}ONG}
12 Platform for meal outside a flat (6,3) LAUNCH PAD {L{A}UNCH} {PAD}
13 Lament for upstart in daybreak (5) MOURN {MO{Up}RN}
15 Little bird given measured food in lab procedure (9) TITRATION {TIT}{RATION}
18 Schematic representation of set of religious principles (9) CATECHISM*
21 Study hard – face university pressure (3,2) MUG UP {MUG} {U}{P}
22 Saloons we renovated when fewer customers would come (3,6) LOW SEASON*
24 Unending sorrow of mean person (5) MISER MISERy
26 Adoration not over for a part of naval fleet (7) WARSHIP W(-o+a)ARSHIP
27 Draw from a little Telugu pamphlet (7) ATTRACT {A}{Te...u}{TRACT}
28 Diversions reportedly perused by that woman's circles (3,8) RED HERRINGS (~read){RED} {HER}{RINGS}

DOWN
1   Replacement for a boy in-charge is very small (9) SUBATOMIC {SUB}{A}{TOM}{IC}
2   What's the purpose of green light? Give up? (5) FORGO {FOR GO}
3   Looking good on the TV, it's time excited niece gets support (9) TELEGENIC {T}{E{LEG}ENIC*}
4   For a little time, rent out small castle (7) FORTLET {FOR}{Time}{LET}
5   Little one accepts eastern doctor to get back on (7) REMOUNT {R{E}{MO}UNT}
6   Health drink – a whole lot to one clinic's head (5) TONIC {TON}{1}{Cl...c}
7   Covering for woman with criminal charge (8) WRAPPING {W}{RAPPING}
8   Dull heavy sound from Doubleday? (4) THUD {THU}{D}
14 French one to have drawback is annoying (8) UNTOWARD {UN}{TO}{DRAW<=}
16 Old school has Indian uncle involved in change (4,5) ALMA MATER {MAMA} in {ALTER}
17 Disease makes one lose head, with spirit destroyed and assuming a bit of hardness (9) NEPHRITIS {oNE}{P{Ha...s}RITIS*}
19 Popular drink I had is tasteless (7) INSIPID {IN}{SIP}{I'D}
20 Official order for fellow's appointment (7) MANDATE {MAN}{DATE}
22 City walls – all is lost – criminals break them (4) LAWS {LA}{WallS}
23 Alien with that woman in cyberspace (5) ETHER {ET}{HER}
25 Dead country, not initially powerful, has a bit of largeness (5) SLAIN S{-p+l}LAIN

GRID